21. Capacitor is a device used to__________
A. store electrical energy
B. vary the resistance
C. store magnetic energy
D. dissipate energy
22. Capacitor stores which type of energy?
A. kinetic energy
B. vibrational energy
C. potential energy
D. heat energy
23. Capacitor blocks__________ after long time.
A. alternating current
B. direct current
C. both alternating and direct current
D. neither alternating nor direct current
24. Why does the capacitor block the dc signal at a steady-state?
A. due to the high frequency of the dc signal
B. due to zero frequency of dc signal
C. capacitor does not pass any current at a steady-state
D. due to zero frequency of dc signal
25. If a parallel plate capacitor of plate area 2m2 and plate separation 1m stores the charge of 1.77 × 10-11 C. What is the voltage across the capacitor?
A. 1V
B. 2V
C. 3V
D. 4V
26. Which of the following is a passive device?
A. Transistor
B. Rectifier
C. Capacitor
D. Vacuum Tubes
27. What is the value of capacitance of a capacitor that has a voltage of 4V and has 16C of charge?
A. 2F
B. 4F
C. 6F
D. 8F
28. For which medium capacitance is high?
A. Air
B. Mica
C. Water
D. Metal
29. The conventional direction of electric field is ________
A. Positive to negative
B. Negative to positive
C. No specific direction
D. Direction cannot be determined
30. Electric field originates at __________
A. Positive charge
B. Negative charge
C. Neither positive nor negative
D. Both positive and negative