MCQ's on Basic 5 Electrical

MCQ's on Basic 5 Electrical

Question 41

If one plate of a parallel plate capacitor is charged with positive charge the other plate is charged to??

  (a) Negative

  (b) Positive

  (c) Not charged

  (d) Either Positive or Negative

The correct answer is (a) Negative

Question 42

When capacitors are connected in parallel what happens to the effective plate area?

  (a) Decreases

  (b) Becomes Zero

  (c) Increases

  (d) Remains same

The correct answer is (c) Increases

Question 43

When capacitors are connected in series, which of the following rules are applied?

  (a) Current divider

  (b) Voltage divider

  (c) Neither Voltage nor Current divider

  (d) Both Voltage and Current divider

The correct answer is (b) Voltage divider

Question 44

For which medium capacitance is high??

  (a) Air

  (b) Mica 

  (c) Metal

  (d) Water

The correct answer is (c) Metal

Question 45

What is the number of primary turns in a 200/1000 V transformer if the emf per turn is 10V?

  (a) 5

  (b) 10

  (c) 20

  (d) 40

The correct answer is (c) 20

The number of primary turns is the ratio of induced emf in the primary to the emf induced per turn. Thus, the number of primary turns in a 200/1000 V transformer with emf per turn of 10V is 200/10 = 20.

Question 46

If the supply frequency is increased keeping voltage constant in Transformer

  (a) eddy current losses will decrease

  (b) hysteresis losses will decrease

  (c) eddy current losses will remain unchanged

  (d) hysteresis losses will remain unchanged.

The correct answer is (c) eddy current losses will remain unchanged

Question 47

Most widely used semiconductor in electronics is

  (a) Mica

  (b) Silicon

  (c) Quartz

  (d) Carbon

The correct answer is (b) Silicon

Question 48

Motor commonly used for traction purpose is

  (a) Induction Motor

  (b) DC shunt Motor

  (c) DC Series Motor

  (d) Synchronous Motor

The correct answer is (c) DC Series Motor

Question 49

How many cycles will an AC signal make in 2 seconds if its frequency is 100 Hz?

  (a) 50

  (b) 100

  (c) 150

  (d) 200

The correct answer is (d) 200

Question 50

What is responsible for the current to flow?

  (a) Protons

  (b) Electrons

  (c) Nucleus

  (d) Protons and Electrons

The correct answer is (b) Electrons

Explanation: For the current to flow in a circuit electrons are required. Electrons are negatively charged and when the potential difference is applied these electrons flow to constitute a current. The current direction is opposite to the electron flow.