MCQ
Choose the incorrect statement:
  • A
    Fleming’s right-hand rule is a simple rule to know the direction of induced current.
  • B
    The right-hand thumb rule is used to find the direction of magnetic fields due to current carrying conductors.
  • C
    The difference between the direct and alternating currents is that the direct current always flows in one direction, whereas the alternating current reverses its direction periodically.
  • D
    In India, the AC changes direction after every $\frac{1}{50}$ second.

Answer

  1. In India, the AC changes direction after every $\frac{1}{50}$ second.

Explanation: Frequency of AC in India = 50Hz

$\therefore$ AC completes 1 cycle in $\frac{1}{50}$ seconds.

In one cycle, AC changes direction two times. Hence, time after which AC changes direction,

$=\frac{1}{2\times50}=\frac{1}{100}\text{ second}.$​​​​​​​

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