Sample 75 Questions | ECE/ECT Board Exam | 2026 — Transcript

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1. 0:01Good day mga ka-CRT. Welcome again to
2. 0:03our YouTube channel.
3. 0:05For this video, meron tayong sample ECE
4. 0:09or ECT review questions.
5. 0:13This will consist of 75 questions and
6. 0:15divided into two parts. Ang first part
7. 0:18puro questions lang. Pero kung gusto
8. 0:20niyong mag-skip na sa first part, pwede
9. 0:23na kayong pumunta sa part two wherein
10. 0:26nandun na yung question and answer.
11. 0:33Let's begin with part one. Again, this
12. 0:35is questions only. Kung gusto niyong
13. 0:39pumunta na sa may questions with answers
14. 0:42or solutions, mag-skip na kayo dito.
15. 0:45I-pass forward niyo na papuntang part
16. 0:48two. Pero sa mga gustong mag-practice,
17. 0:52magsasagot muna kayo ng mga makikita
18. 0:54niyong questions and later cheekan niyo
19. 0:56yung gawa niyo. Referring to the part
20. 1:00two, andun yung mga answers and
21. 1:02solutions.
22. 1:05So for number one the question is what
23. 1:07is the SI unit of electrical charge or
24. 1:11electric charge?
25. 1:17Number two, which of the following can
26. 1:20represent the unit of charge aside from
27. 1:23cou?
28. 1:30Number three, calculate the magnitude of
29. 1:33electric potential at a
30. 1:3610 mm from 1000 electrons.
31. 1:46Number four. Which of the following is
32. 1:49considered as the best conductor of
33. 1:51electricity?
34. 2:00Number 5. What does AWG stand for?
35. 2:13Number six. What is the AWG number for
36. 2:17signaling wires in FD fire detection and
37. 2:21alarm system?
38. 2:29Number 7. The resistance of a copper
39. 2:33with alpha 6.8 * 10-3
40. 2:37per de celus wire is 20 ohms at 20°
41. 2:42Celus. Calculate its resistance at 31°
42. 2:46Celus.
43. 2:53So habang nags-solve kayo, pwede niyo
44. 2:55namang i-post muna yung video then
45. 2:57mag-solve kayo and pag nag-arrive na
46. 2:59kayo sa answer niyo, so pwede niyong
47. 3:02isulat muna yung mga letter of answers
48. 3:05niyo and then later
49. 3:08cheekanyan yung gawa niyo.
50. 3:10Number 8.
51. 3:13A 10 ohm resistor is connected to the
52. 3:16terminals of a battery with a voltage of
53. 3:18240 vols. What is the value of current
54. 3:22in the resistor?
55. 3:31Number nine determine the resistance of
56. 3:34the color coded resistor shown.
57. 3:37So the first digit or the first color is
58. 3:40brown.
59. 3:41Second color black, third orange andth
60. 3:46tolerance
61. 3:49which is gold.
62. 3:57Number 10 determine the resistance of
63. 4:00the color coded resor yellow, violet,
64. 4:04red and silver.
65. 4:08So ayan ang first 10 natin.
66. 4:12I-summarize niyo lang muna yung mga
67. 4:13sagot niyo or i-list down niyo muna yung
68. 4:15mga sagot niyo whether yung letter lang
69. 4:18ang ilagay niyo or yung mismong na-solve
70. 4:21ninyo.
71. 4:25Next 11. What is the CGS unit of
72. 4:29magnetic flux?
73. 4:37Number 12, Tesla is a unit of
74. 4:42pili ka lang diyan A, B, C or D.
75. 4:52Number 13.
76. 4:54If the flux density in a certain
77. 4:56magnetic material is 25 Tesla and the
78. 5:00area of the material is35 s in, what is
79. 5:04the flux through the material?
80. 5:08Pwede mong i-post muna yung video then
81. 5:10i-solve mo yung problem na to.
82. 5:17Number 14 a material that has
83. 5:20permeability
84. 5:21is slightly less than that of space is
85. 5:24called A B C or D.
86. 5:3515
87. 5:36what is the reciprocal of magnetic
88. 5:39reluctance
89. 5:4816 given the circuit find the total
90. 5:51resistance and the total current so wala
91. 5:54ng choices para makapagpractice kayo ng
92. 5:57solving
93. 5:59i-solve niyo yung circuit na
94. 6:05So composed of series parallel
95. 6:08connection.
96. 6:14For number 17, another DC circuit series
97. 6:17parallel combination.
98. 6:19Find the total resistance and total
99. 6:22current.
100. 6:31Number 18. For the circuit, find the
101. 6:34resistance between A and B. So this is
102. 6:37the terminal A and this is the terminal
103. 6:40B. So kung ano yung nasa in between
104. 6:43circuit or in between of A and B,
105. 6:47solveyo yung total resistance.
106. 6:56Number 19.
107. 6:58Again, find the resistance between
108. 7:01terminal A and terminal B.
109. 7:06So this is the terminal A and this is
110. 7:09the terminal B. Ang connected na circuit
111. 7:11diyan purely resistive. So combination
112. 7:14yan ng series and parallel.
113. 7:20Solve niyo 'yan. I-post niyo muna 'yung
114. 7:21video then mag-solve kayo. Pag meron na
115. 7:24kayong RAB, record niyo lang muna 'yung
116. 7:26sagot niyo sa papel. Then later checkan
117. 7:29niyo kapag papanoorin niyo na yung part
118. 7:31two.
119. 7:34Number 20, another DC circuit.
120. 7:38Find the mil voltage and all ice. Soung
121. 7:43ice na to yan yung I1,
122. 7:46I2 and I3.
123. 7:5521
124. 7:56The RMS voltage is 17 volts. Calculate
125. 8:00the pick voltage
126. 8:0822. In pure capacitive circuit, which of
127. 8:12the following is true?
128. 8:15So, pili lang kayo diyan. A, B, C or D.
129. 8:20Then record your answer in
130. 8:23any sheet of paper.
131. 8:2723. What is the si unit of electric
132. 8:32charge?
133. 8:4124.
134. 8:42What is the power factor of a few
135. 8:45resistive circuit?
136. 8:5425.
137. 8:55Calculate the time constant. So ito yung
138. 8:58series RC circuit na tinatawag.
139. 9:0826. What is the unit of apparent power?
140. 9:14So yan ba ay wats, wat ampere, volt
141. 9:17ampere, or volt ampere reactive?
142. 9:2427. What is the value of XL? Given the
143. 9:28series RL circuit.
144. 9:3728 in series resonance which of the
145. 9:40following is true
146. 9:43A
147. 9:44B C or D
148. 9:5329
149. 9:55what is the value of the resonant
150. 9:57frequency
151. 9:58given this series RL and C circuit.
152. 10:14Number 30 what is the charge of the
153. 10:17capacitor at 3 time constant
154. 10:22so check muna yung mga answers from 1 to
155. 10:2530yga
156. 10:28items double check.
157. 10:3331. What do you call the outermost
158. 10:36electron in the figure?
159. 10:39So ito yung outermos electron. In some
160. 10:42cases, more than one ang outermos
161. 10:46electrons. So yan A, B, C or D.
162. 10:5532.
163. 10:56What category of material that is
164. 10:58characterized by having 1 to3 valence
165. 11:02electrons?
166. 11:0933.
167. 11:10What is the energy gap in Germanium?
168. 11:2134.
169. 11:23It is a type of bonding correspond to
170. 11:25the sharing of balance electrons between
171. 11:28two or more atoms.
172. 11:3635. It occurs when a conduction bond
173. 11:39electron loses energy and falls back
174. 11:42into a hole in the balance bond.
175. 11:5136. It is a material produced after
176. 11:55doping silicon with pentavalent atom.
177. 12:0537.
178. 12:07Which of the following is not a type of
179. 12:10trial atom?
180. 12:2138. What is the forward voltage of
181. 12:24gallum arcenide diode?
182. 12:3339.
183. 12:35What do you call the circuit shown?
184. 12:4340. In DC power supply, what is next
185. 12:48after the rectifier?
186. 12:5641. Calculation lang. Walang choices.
187. 13:01The input pick voltage to a half wave
188. 13:04rectifier is 5 vol 60 herz.
189. 13:08Calculate the average value of the
190. 13:10rectified voltage
191. 13:12and the output frequency.
192. 13:16So kung dito hindi binanggit kung anong
193. 13:19diode ang ginamit dito sa rectifier,
194. 13:22ia-assume natin ang silicon diode.
195. 13:2942. The input pick voltage to a full
196. 13:33wave bridge type rectifier is 5 volt 60
197. 13:37herz. Calculate the average value of the
198. 13:41rectified voltage and the output
199. 13:43frequency.
200. 13:47So this time naman full wave ang ginamit
201. 13:50bridge type.
202. 13:56Next 43. Identify the symbol shown.
203. 14:0744.
204. 14:09Also identify the symbol shown.
205. 14:21Number 45. Which of the following diode
206. 14:24is used for high frequency circuits,
207. 14:27switching power supplies, and RF
208. 14:30applications?
209. 14:4046.
210. 14:42who were considered as the inventors of
211. 14:45transistor
212. 14:5347
213. 14:55what are the terminals
214. 14:57of BJT
215. 15:0448 in BJT
216. 15:07which of the following is heavily dop
217. 15:10terminal
218. 15:1949
219. 15:21which of the following is the most
220. 15:23stable DC biasing in BJT
221. 15:3350 which the following is the
222. 15:37characteristic of DJ J.
223. 15:42So naka 50 items na tayo. Double check
224. 15:46niyo yung mga sagot. Double check yung
225. 15:49mga naka-summarize niyong answers and
226. 15:51then later check niyo gamit yung part
227. 15:54two natin. Dun sa part two ng video na
228. 15:56to andun na yung answers and solutions.
229. 16:0451. Which of the following are common
230. 16:07types of FET? Field effect transistor.
231. 16:1652. What are the regions of operation of
232. 16:20BJT?
233. 16:2953. Compared with BJTs,
234. 16:33FTS generally have A, B, C or D.
235. 16:4454 To operate in saturation region, base
236. 16:48emitter junction must be blank and base
237. 16:52collector junction must be blank.
238. 16:56So this is in terms of biasing forward
239. 16:58or reverse ang magiging possible na
240. 17:03pagpipilian natin kada block. So
241. 17:07what is the best answer? A ba c or d?
242. 17:1455.
243. 17:16Which BJT configuration is known for
244. 17:18having moderate or high voltage gain and
245. 17:22moderate current gain
246. 17:26A, B, C or D.
247. 17:3556. Which BJT configuration
248. 17:39has low input impedance and high output
249. 17:42impedance?
250. 17:5257. What is the current gain of
251. 17:56commonbased BJT amplifier?
252. 18:0558. Which of the following is a value
253. 18:09for the Z in or input impedance in
254. 18:12common emiter configuration?
255. 18:2059. Identify the symbol shown.
256. 18:3160 What are the regions of operation of
257. 18:35FET field effect transistor?
258. 18:4661. The insulating layer in mospet
259. 18:50construction is called A, B,
260. 18:54C or D.
261. 19:0162. Which of the following is most
262. 19:04linear class of amplifier?
263. 19:1463.
264. 19:16Which of the following is called pushp
265. 19:19amplifier?
266. 19:2864.
267. 19:29Identify the oscillator shown in the
268. 19:32figure
269. 19:34here.
270. 19:38A, B, C or D.
271. 19:4465.
272. 19:46Which of the following is not a type of
273. 19:49LC feedback oscillator?
274. 19:5766
275. 19:59741 IC is a or an blank?
276. 20:05A, B, C or D.
277. 20:1167.
278. 20:12What is the ideal value of the output
279. 20:15impedance of 741 IC?
280. 20:2668.
281. 20:27What is the gain of the off shown below?
282. 20:3869. In logic circuit, 74 ls08 IC is a
283. 20:45blank gate
284. 20:48and or not X or
285. 20:5670. Which logic gate produces a high
286. 20:59output if and only if the inputs are all
287. 21:04low.
288. 21:05So this is now our number 70. So last
289. 21:09five questions to go. Double check niyo
290. 21:11na yung mga nalista niyo na na sagot or
291. 21:14answers.
292. 21:1771. What is the functional difference
293. 21:20between an SR flip flap and a JK flip
294. 21:24flap?
295. 21:27Check the choices. A, B, C or D.
296. 21:3472. Identify the symbol shown.
297. 21:39So under na ito ng industrial
298. 21:42electronics
299. 21:44A, B, C or D.
300. 21:4973 also identify the symbol shown
301. 22:0074 which of the following do not have
302. 22:04cato terminal
303. 22:11and number 75 which of the following
304. 22:15terminal
305. 22:18A, B, C or D.
306. 22:26So this is the end of the part one. 75
307. 22:29questions only. So, yung kasunod nito
308. 22:31yung part two, babalikan ulit yung lahat
309. 22:34ng questions with answers and solutions
310. 22:38na.
311. 22:42Punta na tayo dito sa part two,
312. 22:45questions, answers and solutions.
313. 22:48So for number one, what is the si unit
314. 22:51of electric charge?
315. 22:54The answer is cou.
316. 22:59Number two, which of the following can
317. 23:01represent the unit of charge aside from
318. 23:04theum?
319. 23:07Number two, which of the following can
320. 23:09represent the unit of charge aside from
321. 23:12couum? So the answer for this is volt
322. 23:17mag tayo ng formula.
323. 23:20Yung formula natin ng Qum's
324. 23:24law is F =
325. 23:27KQ1
326. 23:29Q2 over R S.
327. 23:32Aside from this formula na involve ang
328. 23:34Q, meron din tayong formula na Q = CV.
329. 23:41Okay. So yung Q na cou in terms of
330. 23:45formula this is
331. 23:47this is volt
332. 23:49and this is farad.
333. 23:53So that's why one of the unit na pwede
334. 23:56or equivalent ng cou is volt parad. So
335. 24:00pwede rin yung formula na Q
336. 24:04I T.
337. 24:07So therefore this is
338. 24:10ampere second. So pwede rin yan.
339. 24:17Okay.
340. 24:24And then may isa pa yung Q equ W.
341. 24:29So pwede siyang
342. 24:32joule per bolt.
343. 24:38Okay? So dito sa number two, letter A
344. 24:40lang ang pwede na sagot.
345. 24:46Number 3, calculate the magnitude of
346. 24:48electric potential at a point 10 mm from
347. 24:521000 electrons.
348. 24:55So kung nagsagot kayo sa part 1, ang
349. 24:59sagot natin dito sa part two, 144
350. 25:03microbts and this is the solution.
351. 25:06Gamit ang or related sa
352. 25:10cou law ang pinanggalingan ng formula na
353. 25:12to. voltage equ KQ / R. Yung K constant
354. 25:18yan 9 * 10^ 9 yung Q since 1000 then
355. 25:23yung charge ng electron positive na lang
356. 25:25ginamit since one since magnitude naman
357. 25:28ang tinatanong so instead na - 1.6
358. 25:31positive na to. So for electron charge
359. 25:341.6 * 10^-19
360. 25:371000 pa.
361. 25:40Then yung R the distance. So ito yung 10
362. 25:43na mim pero dapat naka-express in meter
363. 25:47kaya 10 103.
364. 25:50I-solve niyo lang to. You will arrive at
365. 25:52144
366. 25:54micro.
367. 25:58Number 4. Which of the following is
368. 26:01considered as the best conductor of
369. 26:03electricity?
370. 26:06And the answer for this is silver.
371. 26:12Number 5. What does AWG stand for?
372. 26:17Answer is
373. 26:20letter A. American wargage.
374. 26:27Number 6. What is the AWG number for
375. 26:30signaling wars in fire detection and
376. 26:34alarm system?
377. 26:37And this is
378. 26:39letter C number 16.
379. 26:46Okay. So number 7 the resistance of a
380. 26:50copper with alpha of 6.8
381. 26:54103 per cel is ohm at 20° cel calculate
382. 27:01resistance at 31° cel
383. 27:07so the answer for this is 21.5 5 ohms
384. 27:11for the solution. So this is R 1 + alpha
385. 27:18delta T. Yun yung pinakaformula diyan.
386. 27:20Kung ire-recall niyo don't forget this
387. 27:23formula. R
388. 27:26initial 1 + alpha delta t
389. 27:33and you will arrive at 21.496
390. 27:37or 21.5.
391. 27:40So for 7 letter A.
392. 27:47Number 8.
393. 27:49A 10 ohm resistor is connected to the
394. 27:51terminals of battery with voltage of 240
395. 27:54volts. What is the value of current in
396. 27:57the resistor? So ito ohms low lang kaya
397. 28:01the answer is 24 amp. Ito iyung
398. 28:04solution. V / R lang.
399. 28:07So 240 / 10 is 24.
400. 28:15Number 9. Determine the resistance of
401. 28:18the color coded resistor shown in the
402. 28:21picture below.
403. 28:23So brown is one, black is zero. And then
404. 28:27yung orange multiplier na 1,000. Gold is
405. 28:315%.
406. 28:33So the answer for this is letter C
407. 28:3710,000 ohms or 10 kohms plus and minus
408. 28:415%.
409. 28:47For number 10 determine the resistance
410. 28:50of the color coded resistor yellow
411. 28:53violet red silver.
412. 28:58And this is letter D.
413. 29:014.7 kohms plus and minus 10%.
414. 29:10Number 11. What is the CGS unit of
415. 29:14magnetic flux?
416. 29:16The answer for this
417. 29:18is Maxwell.
418. 29:21So kapag SI unit yan ang sagot Weber.
419. 29:27Number 12. Tesla is a unit of
420. 29:34the answer is letter D magnetic flux
421. 29:38density
422. 29:4113
423. 29:43if the flux density in a certain
424. 29:45magnetic material is 25 Tesla and the
425. 29:48area is35 s in what is the flux
426. 29:53so kung nagsagot kayo kanina sa part
427. 29:56aabangan niyo na lang 'yung sagot natin
428. 29:58dito And this is letter B 56.5 microaper
429. 30:04for the solution. So ang formula ng flux
430. 30:07ay B A yung Tesla times the area. Pero
431. 30:12yung area dapat naka-square meter. So
432. 30:15magkaroon kayo ng conversion diyan. And
433. 30:18this is the complete solution. You will
434. 30:20arrive at 56.48
435. 30:23or 56.5
436. 30:25microwave.
437. 30:29Number 14 a material that has
438. 30:31permeability slightly less than that of
439. 30:34prespace is called
440. 30:37letter A diamnetic.
441. 30:41Itong diamnetic these are the materials
442. 30:44that are not attracted by magnet.
443. 30:47Examples gold and silver.
444. 30:54Next number 15 the reciprocal of
445. 30:57magnetic reluctance is called
446. 31:03letter D perme
447. 31:10number 16
448. 31:12find the total resistance so magsisimula
449. 31:15tayo dito
450. 31:18so series ang connection niyan
451. 31:21Therefore, 8 + 4 = 12 ohms.
452. 31:26Then itong dalawa
453. 31:2912 i-parallel niyo sa 12. So paano ang
454. 31:31solution niyan? Kapag dalawa lang, pwede
455. 31:33kayong gumamit ng product over
456. 31:37sum.
457. 31:39O kaya yung shortcut kapag yung
458. 31:41naka-parallel equal value, idi-divide mo
459. 31:45lang kung ilan yung naka-parallel. In
460. 31:47this case, dalawang 12 / 2. Kung tatlong
461. 31:5012 yan, divid by 3. So this is 12 div 2
462. 31:55ang gagamitin. So 6 ohms.
463. 31:58And then itong 6 na to magiging series
464. 32:01yan dito sa R1.
465. 32:04Therefore, ang R total natin 6+ 6 12
466. 32:10ohms.
467. 32:13For the total current ohms na lang to.
468. 32:16VT over RT. So we have 12 volts. Given
469. 32:20naman yung 12 volts over 12 ohms. So
470. 32:26this is 1 amp.
471. 32:32Number 17.
472. 32:35So ito muna iso-solve natin.
473. 32:38Naka-parallel yan. So 100
474. 32:42250
475. 32:44/ 100 + 250.
476. 32:51So this is 500
477. 32:55over 7 ohms. Ito naman parallel din.
478. 32:59Gamitan natin ng product
479. 33:02over sum.
480. 33:11So ito naman 1,
481. 33:15ohms. So yung total resistance natin
482. 33:19ia-add lang natin yan.
483. 33:26And this is
484. 33:29pwede ng mag-decimal.
485. 33:32Okay. 198.
486. 33:3570 kung two decimal places
487. 33:40for the total current
488. 33:4424 volts yan ang total voltage
489. 33:48over
490. 33:50198.7 7.
491. 33:58So the answer is 12 amp.
492. 34:07So for number 18 dito kung io-observe
493. 34:09niyo this is point A. Pag tinrace mo
494. 34:13yan, ito point A din.
495. 34:16Ito point A din.
496. 34:18Ito naman pag tinrace mo this is point B
497. 34:22then extend mo rito.
498. 34:25Point B rin to. Kung makikita niyo yung
499. 34:28bawat resistor itong 15 ohms between A
500. 34:32and B. Itong another 15 ohms between A
501. 34:36and B rin siya. And this 15 ohms between
502. 34:40A and B rin. So kung ilalatag natin yan
503. 34:44na pare-parehas silang between A and B.
504. 34:49So connected yung one side nila sa A.
505. 34:52Yung kabilang side nila connected
506. 34:54pare-parehas din sa B. That's why this
507. 34:57is simply
508. 34:59three resistors in parallel.
509. 35:03And kung naka-parallel then pare-parehas
510. 35:06yung total resistance niyan pwedeng
511. 35:10shortcut ' ba yung R divided by kung
512. 35:12ilan yung naka-parallel.
513. 35:14So in this case 15 ohms and then tatlo
514. 35:18sila. Our answer is simply
515. 35:215 ohms. So yan ba yung sagot niyo kanina
516. 35:26sa part one? ' Ba part one natin
517. 35:28pinakita muna natin lahat ng questions
518. 35:31and then dito sa part two, nandito na
519. 35:33yung mga answers with solutions.
520. 35:38So next number 19
521. 35:41find RAB again. So, dito naman dadalhin
522. 35:45natin iyung solution papunta rito sa
523. 35:47terminals na to. Iisa-isahin natin yan.
524. 35:51Ito ay naka-series
525. 35:536 ohms yan. Then
526. 35:58ito tsaka ito
527. 36:01parallel connection yan.
528. 36:04So ang makukuha niyo dito 3 ohms.
529. 36:07Okay?
530. 36:09Then anong gagawin diyan sa 3 ohms na
531. 36:10yan? Dito na yung next connection yan.
532. 36:14So naka-series 3 + 3 = 6 ohms na naman.
533. 36:20Itong 6 ohms na to dadalhin mo rito yan.
534. 36:25Anong connection?
535. 36:27Parallel. 6 parallel with 6. So dalawang
536. 36:31parehas idi-divide mo lang sa 2 3 ohms
537. 36:37' ba. So itong 3 na yan
538. 36:40naka-series dito yan sa 3 tsaka sa 3.
539. 36:43Kaya dito
540. 36:48equivalent yan sa 3 + 3 + 3 8 ohms pala
541. 36:52to yung equivalent niyan.
542. 36:57Okay.
543. 36:59So the equivalent series connection
544. 37:03up to this point is 8 ohms. Then
545. 37:06naka-parallel to.
546. 37:088 parallel with 8 is 4.
547. 37:14So anong gagawin sa 4? Isi-series dito
548. 37:17yan.
549. 37:18Therefore, RAB natin is simply 4 + 2
550. 37:24or 6 ohms. Yan ba ang sagot niyo kanina
551. 37:26sa part 1?
552. 37:32Okay. For number 20, find the mil
553. 37:35voltage and all eyes. So yung mil
554. 37:38voltage gawin nating BM.
555. 37:42Recall natin ang formula. This is B1
556. 37:45over R1.
557. 37:48+ b2
558. 37:50/ r2
559. 37:53+ b3 / r3 and so on. Idi-divide natin
560. 37:58yan sa inverse ng resistance or
561. 38:01summation ng inverse ng resistance na 1
562. 38:04/ 1 + 1 / 2 + 1/3 and so on kung may mga
563. 38:13iba pang branch.
564. 38:15So dalhin natin dito ang solution.
565. 38:18Therefore, this is BM.
566. 38:21So
567. 38:24ang B1 or ang first branch natin dito
568. 38:26natin kukunin.
569. 38:29Ang voltage diyan is 10 volts over ang
570. 38:32resistance diyan 10 ohm
571. 38:35plus.
572. 38:38Okay, ito naman
573. 38:41walang voltage source dito. So this is
574. 38:45zero over the resistance dian sa branch
575. 38:49na yan 40 ohms.
576. 38:52Plus dito naman sa third branch ang
577. 38:55voltage
578. 38:5620 volts over yung resistance sa branch
579. 38:59na yan 20 ohms. So ito na ngayon yung
580. 39:04pinapahanap na mil voltage.
581. 39:11Ah kulang pa pala yan. Meron pang
582. 39:14denominator pa pala.
583. 39:17So numerator pa lang yan. over 1 / 10
584. 39:21ohms + 1/ 40 ohms + 1 / 20 ohms. So
585. 39:27i-solve lang muna natin. เ
586. 40:01So the answer here is 80 /7.
587. 40:05Kapag dinecimal niyo 11.43
588. 40:10vols.
589. 40:20Okay. So para naman ma-solve yung I1,
590. 40:26ito yung solution. Bale 'yung 10 volts
591. 40:28ima-minus lang natin 'yung mil. So this
592. 40:31is 10 - 11.43
593. 40:36over
594. 40:3810 ohms.
595. 40:45So - 0.143
596. 40:48a.
597. 40:50So kaya negative yan ibig sabihin
598. 40:55baliktad lang 'yung arrow. So instead
599. 40:56not to the right
600. 41:00'yung flow ng
601. 41:02143 dapat to the left.
602. 41:07Yun lang naman ibig sabihin.
603. 41:10For I2
604. 41:12kanina walang voltage pero dito
605. 41:14magso-solve na tayo ng I. Ang gagamitin
606. 41:17niyo yung meal months. 11.43 43 over the
607. 41:21resistance yung 40 ohms
608. 41:28kung 3 decimal din to286
609. 41:33amp
610. 41:37then for i3
611. 41:40so
612. 41:42yung 20 volts na to
613. 41:45magma-minus ulit tayo ng mil months
614. 41:4811.43 over nung sa resistance diyan na
615. 41:5220 ohms.
616. 42:03So this is 0.4285
617. 42:05gawin ko ng 429.
618. 42:09So yan yung mga sagot natin for this
619. 42:10number 20.
620. 42:16Next for number 21, the RMS voltage is
621. 42:1917 volts. Calculate the pick voltage.
622. 42:24So ang sagot dito letter D 24 vol. For
623. 42:28the solution, this is simply
624. 42:31yung RMS i-multiply mo ang SO 2 to get
625. 42:35the pick voltage.
626. 42:37So this is 24.04.
627. 42:39sa choices 24 volts
628. 42:4522 in pure capacitive circuit which of
629. 42:49the following is true so ano ba yung mga
630. 42:51pinag-uusapan diyan yung lead and log
631. 42:54ano ba yung nauuna yung current ba o
632. 42:57yung voltage at kung may nauun may
633. 43:00nahuhuli in terms of degrees ilan yung
634. 43:03value
635. 43:05okay so pure to the answer
636. 43:09I leads A or the voltage by 90°.
637. 43:15Magiging less than 90° yan kapag yung
638. 43:18capacitor may kasama ng resistor.
639. 43:25So ito sa capacitor kapag inductor or
640. 43:28pure inductive babaliktad lang yan. E
641. 43:30leads I naman yon. Okay. Kaya dito
642. 43:33tatandaan natin yung nemonics na Ellie
643. 43:38the Ice Man.
644. 43:41So kapag inductive circuit nauuna yung
645. 43:43E. Kapagka positive circuit nauuna yung
646. 43:46I.
647. 43:50Number 23. Ano sagot niyo rito? Parang
648. 43:52naulit lang to. What is the si unit of
649. 43:55electric charge? Naulit lang onong item
650. 43:57na to or yung question. Ang sagot dito
651. 43:59ay letter B.
652. 44:0524 na tayo. What is the power factor of
653. 44:07pure resistive circuit? The answer for
654. 44:10this
655. 44:12is one. Kapag pure inductive yan or
656. 44:15capacitive zero. Kapag naman magkahalo,
657. 44:20kapag RL or RC or RLC between 0 to 1.
658. 44:25Walang greater than 1 na power factor.
659. 44:3025.
660. 44:32Calculate the time constant. Simple lang
661. 44:34naman. Simple RC circuit.
662. 44:39So ang answer dito letter D 7.5 mcs.
663. 44:45Simple solution is imu-multiply niyo
664. 44:48lang yung R and C. So 500
665. 44:52micro is 7.5
666. 44:54milliseconds.
667. 44:5826. What is the unit of apparent power?
668. 45:04The answer is volt ampere.
669. 45:07So yung true power what's ang unit? Yung
670. 45:11reactive power ito naman yung unit. Volt
671. 45:15ampere reactive or bar. Kapag apparent
672. 45:19volt ampere.
673. 45:2327 what is the value of XL? So yung XL
674. 45:27inductive reactance.
675. 45:31And the answer for this
676. 45:34is none from the choices. Kaya kung
677. 45:35nag-solve kayo sa part one, baka
678. 45:37nagtataka kayo wala sa choices yung
679. 45:39sagot. So hindi nailagay yung correct
680. 45:42answer. Ang solution kasi dito, XL = 2π
681. 45:47FL. So 2π times the frequency. Andiyan
682. 45:50naman ang frequency 60. And yung L itong
683. 45:555. Henry.
684. 45:56So the correct answer for number 27 is
685. 45:59188.5.
686. 46:0528. In series resonance which of the
687. 46:08following is true? So the answer for
688. 46:11this
689. 46:13equal angl.
690. 46:17So letter A for number 28.
691. 46:2329. What is the value of the resonant
692. 46:26frequency?
693. 46:30So the answer is 161.2
694. 46:34and the solution is 1 2π roc.
695. 46:40L is 650 milenry
696. 46:43C is 1.5 microfarad.
697. 46:47So this is the answer 161.2 2
698. 46:5530 What is the charge of the capacitor
699. 46:59at three time constant? Itong symbol na
700. 47:01to dito sa
701. 47:04capacitor this is time constant.
702. 47:07So the answer for this at three time
703. 47:09constant ang charge na ng capacitor 95%.
704. 47:14For your reference, ito yung mga ito
705. 47:17yung table. Kapag one time constant 63%
706. 47:21286 395
707. 47:24498 and 5 99%.
708. 47:3031 what do you call the outermost
709. 47:32electron in the figure?
710. 47:36Balance electron. Letter B.
711. 47:4132. What category of material that is
712. 47:44characterized by having 1 to3 valence
713. 47:47electron?
714. 47:51This is letter A conductor.
715. 47:5733 what is the energy gap in Germanium?
716. 48:02So the unit is electron volt. And this
717. 48:05is 67 electron volt.
718. 48:11For your reference sa germanium again67
719. 48:14sa silicon 1.1 sa gum arsenide 1.43
720. 48:19electron volt. Ang tawag diyan ay energy
721. 48:23gap.
722. 48:2634 it is a type of bonding correspond to
723. 48:29the sharing of balance electrons between
724. 48:31two or more atom.
725. 48:35Answer for 34 is letter C. Covalent
726. 48:38bonding.
727. 48:4435 it occurs when conduction band
728. 48:47electron loses energy and falls back
729. 48:50into the hole in the balance band.
730. 48:54Answer is recombination.
731. 49:0236. It is a material produced after
732. 49:05doping silicon with pentavalent atom. So
733. 49:10pinaghalo ang silicon and pentavalent
734. 49:12atom. Ang mapo-produce natin diyan
735. 49:17type material.
736. 49:20Letter D for number 36.
737. 49:2537 Which of the following is not a type
738. 49:29of trialent atom?
739. 49:33The answer is
740. 49:35letter D Germanium. So ibig sabihin yung
741. 49:37boron, indium and galum lahat yan
742. 49:41considered tribalent atom.
743. 49:4638. What is the forward voltage ofum
744. 49:50arsenite diode?
745. 49:53The answer for number 38 is letter D 1.2
746. 49:58vol. For your reference Germanium3,
747. 50:02silicon7,
748. 50:04selenium 1.0 and gallum arcenite 1.2.
749. 50:11So other name for the forward voltage is
750. 50:14knee voltage.
751. 50:1939. What do you call the circuit shown?
752. 50:23So medyo nahuli lang. And this is the
753. 50:26answer. Letter A clipper.
754. 50:34Number 40. In DC power supply, what is
755. 50:37next after directifier?
756. 50:40Answer for number 40 is filter. And for
757. 50:43your reference, ito yung
758. 50:44pagkakasunod-sunod.
759. 50:46So meron kang AC supply, then
760. 50:49transformer,
761. 50:51rectifier, followed by filter,
762. 50:54regulator, and output.
763. 50:57So naka-40 items na tayo na pinakita
764. 51:00yung mga sagot. Pwede nyong i-check muna
765. 51:02'yung mga nasagutan niyo. Bilangin niyo
766. 51:05'yung scores nyo. Double check niyo kung
767. 51:08umabot na ba kayo ng 70%. 70 ang passing
768. 51:11natin sa ECE or ECT board exam. So ano
769. 51:17ba ang 70% ng 40? 28. So kung naka 28
770. 51:22correct points na kayo passing score
771. 51:25yan.
772. 51:27Proceed na tayo.
773. 51:3041. Ito calculation. Walang choices.
774. 51:32Check niyo na lang yung mga sagot.
775. 51:35The input pick voltage to a half wave
776. 51:37rectifier is 5 volts. So ito pa lang
777. 51:40yung papasok sa rectifier. Pag dumaan
778. 51:43yan sa rectifier, pagkalabas niyan, may
779. 51:45voltage drop sa rectifier. And this is
780. 51:497.
781. 51:51Then itong 7 ang kukuha na natin ng
782. 51:54average value for half wave. This is BP
783. 51:59over pi.
784. 52:01So the answer for
785. 52:03the average value of the rectified
786. 52:06voltage is 1.37 vol. And for the output
787. 52:10frequency,
788. 52:12equal lang kung ano yung input. So kung
789. 52:1460 herz ang input the output is also 60
790. 52:18herz.
791. 52:2342 ginawa lang ong full wave and gumamit
792. 52:26ng bridge type. So sa bridge type may
793. 52:30voltage drop din and this is 1.4 ang
794. 52:33voltage drop.
795. 52:36Kaya yung lumabas sa bridge type
796. 52:39rectifier 3.6 na lang. And iso-solve
797. 52:43natin yung average niyan kapag full wave
798. 52:472bp over.
799. 52:49So the result for the average voltage
800. 52:522.29 volts and for the output frequency
801. 52:56times 2 naman dito kapag full wave. So
802. 53:00the output frequency is 120 herz.
803. 53:0743 Identify the symbol shown.
804. 53:12This is zener di
805. 53:1744 also identify the symbol shown
806. 53:22the answer for this is letter B tunnel
807. 53:26diode
808. 53:28and for your quick reference andyan ang
809. 53:31PN diode.
810. 53:34It should be pin. P pin diode. Ito pin
811. 53:36diode 'to.
812. 53:40Then zenner,
813. 53:42LED, Scot key, tunnel, photodiode and
814. 53:47baractor diode.
815. 53:5345. Which of the following diode is used
816. 53:56for high frequency circuits, switching
817. 53:59power supplies, and RF applications? The
818. 54:03answer for number 45 is Scott Key Diode.
819. 54:09For your quick reference, ito yyung mga
820. 54:11special purpose diode and yung mga
821. 54:13application nila.
822. 54:2046. who were considered as the inventors
823. 54:23of transistor
824. 54:26answer for number 46 is letter D.
825. 54:30William Shakley,
826. 54:32John Bardin and Walter Ratin.
827. 54:3947
828. 54:40what are the terminals of BJT?
829. 54:45And this is letter A emiter, base and
830. 54:49collector.
831. 54:5448 in BJT which of the following is
832. 54:57heavily dope
833. 55:02this is emiter
834. 55:05moderately dope collector lightly dope
835. 55:08bas
836. 55:1149 which of the following is the most
837. 55:14stable DC biasing in BJT
838. 55:19this is letter C voltage divider bias
839. 55:28Number 50. Which of the following is the
840. 55:31characteristic of BJT?
841. 55:36The answer for number 50 is letter A.
842. 55:39Current controlled device. So ang BJT
843. 55:42bipolar yan and hindi naman siya
844. 55:46sensitive sa ESD kaya hindi rin to
845. 55:49pwedeng all of the above. So again
846. 55:52letter A for number 50
847. 55:5751 which of the following are common
848. 55:59types of F
849. 56:03this is JPET and Mospet letter C
850. 56:0852 what are the regions of operation of
851. 56:11BJT
852. 56:14this is saturation cut and active region
853. 56:2253 compared with BJTs, Fet generally
854. 56:27have
855. 56:30higher input impedance.
856. 56:32So dito sa part two, medyo mabilis lang
857. 56:34ano dahil nga sa part one nandun yung
858. 56:37nagbabasa pa kayo, nag sasagot kayo and
859. 56:40dito sa part two nire-reveal na lang
860. 56:42yung mga sagot. And kung kailangan ng
861. 56:44solution, pinapakita ko rin naman. Okay.
862. 56:4854.
863. 56:50To operate in saturation region, base
864. 56:53emitter junction must be blank bias and
865. 56:56base collector junction must be blank
866. 56:59bias. Kapag saturation, ang sagot diyan
867. 57:03parehas na forward.
868. 57:06Okay? Kapag active forward reverse
869. 57:11yan. Kapag cut off region
870. 57:14basta naka-reverse
871. 57:16'yung base emiter.
872. 57:19Cut of region na yon.
873. 57:2355. Which BJT configuration is known for
874. 57:26having moderate to high voltage gain and
875. 57:29moderate current gain?
876. 57:32This is common emiter configuration.
877. 57:3956.
878. 57:41Which BJT configuration has low input
879. 57:44impedance and high output impedance?
880. 57:4956 letter C common base.
881. 57:5657. What is the current gain of common
882. 57:59base amplifier?
883. 58:03Kapag common base
884. 58:07alpha
885. 58:09kapag
886. 58:11common collector gamma.
887. 58:13Okay? Tandaan natin yan ha. Itong alpha
888. 58:17common base, beta common emiter and
889. 58:21gamma common collector.
890. 58:2758. Which of the following is a value
891. 58:30for input impedance in common emiter
892. 58:33configuration?
893. 58:35Kapag input impedance, moderate lang to
894. 58:38sa common emiter.
895. 58:41So dito
896. 58:44answer is letter B.
897. 58:461 kohms
898. 58:5059 Identify the symbol shown symbol to
899. 58:54ng one type of fet
900. 58:57and the answer for this yan kung
901. 59:00titingnan niyo yung arrow palabas sa
902. 59:03center P channel yan
903. 59:06so pipili na lang tayo sa A tsaka sa C
904. 59:09and the answer is os kasi putol-putol
905. 59:12yung dito kapag yan straight line, solid
906. 59:16line,
907. 59:18depletion, mospet yan. Pero pag
908. 59:19putol-putol,
909. 59:21enhancement or emos.
910. 59:2660 what are the regions of operation of
911. 59:30Fet?
912. 59:32And this is
913. 59:34OMIC saturation and cutof.
914. 59:4461.
915. 59:46The insulating layer in mospet
916. 59:48construction is called
917. 59:51silicon dioxide. So ito yun yung
918. 59:54naka-stripe na to. Silicon dioxide yan.
919. 59:59So yung symbol niyan si O2.
920. 1:00:05Yan yung nagpapataas ng input impedance
921. 1:00:08ng mospet. Yang layer na yan.
922. 1:00:12Okay. So 62, which of the following is
923. 1:00:15most linear class of amplifier?
924. 1:00:18So kapag most linear na na-consider yung
925. 1:00:21amplifier, yan yung class A. So 62
926. 1:00:25letter A yung sagot natin.
927. 1:00:3063. Which of the following is called
928. 1:00:33pushpol amplifier?
929. 1:00:35Kapag pushp.
930. 1:00:4264
931. 1:00:43identify the oscillator shown anong
932. 1:00:46tawag diyan sa oscillator na yan this is
933. 1:00:48called
934. 1:00:50pay shift oscillator. Isang klase ng RC
935. 1:00:54feedback oscillator.
936. 1:00:5965. Which of the following is not a type
937. 1:01:02of LC feedback oscillator?
938. 1:01:07So Y and bridge kasi yyung Heartley Clap
939. 1:01:10Colpits mga LC feedback oscillator yan
940. 1:01:13yung Yen Bridge Payshift 20 Yen Bridge
941. 1:01:18Payshift 20 mga ano yan RC feedback
942. 1:01:20oscillator
943. 1:01:2566 74
944. 1:01:27or 741 IC anong CL klaseng IC yan
945. 1:01:32ay general purpose of
946. 1:01:3867 what is the ideal value of the output
947. 1:01:41impedance of 741 or nung off amp ideal
948. 1:01:47zero 67 letter C
949. 1:01:5368 what is the gain of the off amp shown
950. 1:01:56so naka-inverting configuration Siya
951. 1:02:00sagot diyan - 5.
952. 1:02:03Ito 'yung solution.
953. 1:02:05AB = - RF / RI.
954. 1:02:09So 100 / 20 lang. Therefore -5.
955. 1:02:1569 in logic circuit 74 ls08 IC. Anong
956. 1:02:20klaseng logic gate yan? Titingnan niyo
957. 1:02:23lang naman diyan yung dulo. 08.
958. 1:02:27This is gate
959. 1:02:3270. Which of the following gate produces
960. 1:02:34a high output if and only if the inputs
961. 1:02:38are all low?
962. 1:02:42Answer is Norge.
963. 1:02:47So i-recall niyo, review yung truth
964. 1:02:50table ng mga logic gate. Lumalabas yan
965. 1:02:53sa board examinion.
966. 1:02:5771. What is the functional difference
967. 1:03:00between SR flip flap and JK flip flap?
968. 1:03:06So yung JK
969. 1:03:08no invalid state. Nangyayari yan kapag
970. 1:03:12ang value ng input ay 11. 'Di ba? Sa SR
971. 1:03:16kapag 11 ang input invalid. Pero sa JK
972. 1:03:20kapag one ang input
973. 1:03:23the result is toggle.
974. 1:03:25So 71 letter C
975. 1:03:3072 industrial electronics devices
976. 1:03:34identify the symbol anong sagot niyo sa
977. 1:03:3772?
978. 1:03:40This is triac
979. 1:03:42letter B 72 letter B
980. 1:03:4773
981. 1:03:49again identify the symbol industrial
982. 1:03:51electronics device
983. 1:03:5373 Three letter A unijunction transistor
984. 1:03:57or UJT.
985. 1:04:0174 Which of the following do not have
986. 1:04:04cathode terminal?
987. 1:04:06So kung aaralin niyo ang mga devices sa
988. 1:04:10industrial electronics, aalamin niyo
989. 1:04:12yung mga terminals.
990. 1:04:1474 answer is UJT.
991. 1:04:18Okay?
992. 1:04:20So alaminyo yung mga terminals and
993. 1:04:22symbol ng mga yan. PUT UJT SCR GTO
994. 1:04:2875 which of the following has four
995. 1:04:31terminals
996. 1:04:33SCR ba SBS SCS or Triac?
997. 1:04:38So SCS ito yun SCR tatlo lang SBS tatlo
998. 1:04:44din Triac tatlo din yan SCS ap 75 letter
999. 1:04:54And this is the end of sample ECE EC
1000. 1:04:57review 75 questions
1001. 1:05:00good luck and God bless E or EC board
1002. 1:05:04exam media see you in our next video
1003. 1:05:08lectures orample
1004. 1:05:10ECE or EC vi