MCQ
2241. The electric current is due to the flow of--
positive charges only
negative charges only
both positive and negative charges
neutral particles only
2242. How many watt-hours represent 65 W used for 18h?
11.7Wh
11,700Wh
1.170Wh
117,000Wh
2243. Out of the following which is not a poor conductor?
Cast iron
Carbon
Copper
Tungsten
2244. An electric fan and a heater are marked as 100W, 220V and 1000W, 220V respectively. The resistance of heater is-
zero
greater than that of fan
less than that of fan
equal to that of fan
2245. When resistance element of a heater fuses and then we reconnect it after removing a portion of it, the power of the heater will-
decrease
remain constant
increase
none of the above
2246. A 15 V source is connected across a 12 resistor. How much energy is used in three minutes?
938Wh
56.25Wh A
0.938Wh
5.6Wh
2247. প্যার্টানে ড্রাফট কেন ব্যবহার করা হয়?
Remove pattern hardly
Remove pattern easily
Remove pattern quickly
কোনোটিই নয়
2248. Relative permeability of vacuum is-
4π10^-7 H/m
1H/m
1/4π
1
2249. A 1k, 1W resistor can safely pass a current of-
31.62mA
100mA
150 mA
500 mA
2250. মাল্টি প্রসেস/মাল্টি পজিশনিং ওয়েন্ডিং পদ্ধতি কোনটি?
Seam
Soldering
Projection
কোনোটিই নয়
2251. Which is the lightest particle of an atom?
Neutron
Proton
Electron
All have same weight
2252. It becomes more difficult to remove-
any electron from the orbit
first electron from the orbit
second electron from the orbit
third electron from the orbit
2253. The number of electron in the outermost orbit of carbon atom is-
8
2
4
6
2254. Ampere second could be the unit of-
Power
Energy
Conductance
Charge
2255. The unit of absolute permitivity of a medium is-
joule/coulomb
Newton meter
farad/meter
farad/coulomb
2256. Which of the following materials has a negative temperature co-efficient of resistance?
Insulator
Conductor
Semiconductor
None of them
2257. What is the unit of work?
Newton
Watt
Joule
Pascal
2258. Which of the following material has nearly zero temperature co-efficient of resistance?
Manganin
Carbon
Porcelain
Copper
2259. সাবমার্জড আর্ক ওয়েল্ডিং কোনটি ব্যবহৃত হয়?
Blanket flux
Basic flux
Luminous flux
Electric flux
2260. A length of wire has a resistance of 6 ohms. The resistance of a wire of the same material three times as long and twice the cross sectional will be-
36 ohms
9 ohms
1 ohms
12 ohms