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 ?

Related Mcqs:

1. 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

2. 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

3. 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

4. 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 ?

   A. 220V
   B. 220/ 2V
   C. 110V
   D. 220 √2V

5. When A.C current passes through a capacitor then the current relationship will be_______________?

   A. The current lead voltage by phase angle is 90 degrees
   B. The voltage leads current by phase angle is 90 degrees
   C. The current lead voltage by phase angle is 45 degrees
   D. The voltage leads current by phase angle is 45 degrees

6. If capacitance of L-C circuit is made four times then frequency of the circuit becomes___________________?

   A. Twice
   B. One half
   C. Four times
   D. None

7. The frequency of a circuit consisting of a capacitance C and a resistor R is________________?

   A. C/R
   B. R/C
   C. 1/RC
   D. 1/ 2RC

8. In an X-ray tube electrons each of charge e are accelerated through V potential difference allowed to hit a metal target. The wavelength of the X-rays emitted is_______________?

   A. he/ev
   B. he/Vc
   C. eV/h
   D. impossible to predict

9. According to equation of continuity A1V1 = A2V2 = constant. The constant is equal to_______________?

   A. Flow rate
   B. Volume of fluid
   C. Mass of fluid
   D. The density of the fluid

10. Boltzman constant K in terms of universal gas constant R and Avagadros number Na is give as_______________?

    A. K = RNa
    B. K = R/Na
    C. K = Na/Ra
    D. K = nRNa