A 10Ω electric heater is connected to a 220V 50Hz mains supply. What is the peak value of the potential difference across the heater element ?

Related Mcqs:

1. Three bulbs are rating 40W 60W and 100W designed to work on 220V mains. Which bulb will burn most brightly if they are connected in series across 220 V mains ?

   A. 40 W bulb
   B. 60 W blub
   C. 100 W blub
   D. all will burn equally brightly

2. An alternating current of the r.m.s value of 4.0 A and frequency 50Hz flows in a circuit containing a 10Ω resistor. The peak current is then ?

   A. 20A
   B. 20.66A
   C. 6.66A
   D. 5.66A

3. When a pure inductor of inductance L and a pure capacitor of capacitance C are connected in parallel to a sinusoidal potential difference V the potential difference across both L & C will be_______________?

   A. Same
   B. Different
   C. At L will be more than at C
   D. At L will be less than at C

4. n an LCR series circuit, if V is the effective value of the applied voltage VR is the voltage across R VL is the effective voltage across L & Vc is the effective voltage across C then_______________?

   IA. V = VR+VL+VC
   B. V2 = VR2+VL2+VC2
   C. V2 = VR2+(VL-VC)2
   D. V2 = VL2+(VR-VC)2

5. Three equal resistors connected in series with a source of e m f together dissipate 10 W of power each. What will be the power dissipated if the same resistors are connected in parallel across the same source of e m f ?

   A. 40 W
   B. 90W
   C. 100W
   D. 120W

6. A capacitor of capacitance 30µF is charged by a constant current of 10mA. If initially, the capacitor was uncharged what is the time taken for the potential difference across the capacitor to reach 300V ?

   A. 0.9sec
   B. 15 sec
   C. 1.5x105sec
   D. 0.9x102sec

7. A 100µF capacitor with a 12V source in series having frequency 50Hz will offer a capacitive reactance of about______________?

   A. 32Ω
   B. 62Ω
   C. 50Ω
   D. 100Ω

8. A moving coil galvanometer of resistance 100? gives half scale deflection for a current of 20mA. What will be the potential difference across it ?

   A. 4 volt
   B. 5 volt
   C. 2 volt
   D. 0.4 volt

9. Waves produced at the surface of water by a pencil executing vibrating motion if held vertically at a frequency of 50Hz are__________________?

   A. Longitudinal
   B. Transverse
   C. Periodic
   D. both A and C

10. An immersion heater of 400 watts kept on for 5 hours will consume electrical power of __________________?

    A. 2KWh
    B. 20KWh
    C. 6KWh
    D. 12KWh