MCQ
1. 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
2. Relative permeability of vacuum is-
4π10^-7 H/m
1H/m
1/4π
1
3. Which is the lightest particle of an atom?
Neutron
Proton
Electron
All have same weight
4. A 1k, 1W resistor can safely pass a current of-
31.62mA
100mA
150 mA
500 mA
5. 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
6. 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
7. The main objectives of electrical power transmission is/are-
Transmission system must be more efficient with minimum line losses
Voltage regulation of the transmission line must be zero or minimum
both 1 and 2
neither I nor 2
8. Which of the following material has nearly zero temperature co-efficient of resistance?
Manganin
Carbon
Porcelain
Copper
9. What is the unit of work?
Newton
Watt
Joule
Pascal
10. Out of the following which is not a poor conductor?
Cast iron
Carbon
Copper
Tungsten
11. Ampere second could be the unit of-
Power
Energy
Conductance
Charge
12. Which of the following materials has a negative temperature co-efficient of resistance?
Insulator
Conductor
Semiconductor
None of them
13. How many watt-hours represent 65 W used for 18h?
11.7Wh
11,700Wh
1.170Wh
117,000Wh
14. 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
15. One Newton meter is same as-
one watt
five joules
one joule
one joule second
16. The electric current is due to the flow of--
positive charges only
negative charges only
both positive and negative charges
neutral particles only
17. 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
18. The unit of absolute permitivity of a medium is-
joule/coulomb
Newton meter
farad/meter
farad/coulomb
19. ট্রান্সলে পদ্ধতির রেটিং কত?
11KV
33kV
22kV
66kV
20. The number of electron in the outermost orbit of carbon atom is-
8
2
4
6