Question

If the frequency of an alternating current is 50 Hz then the time taken for the change from zero to positive peak value and positive peak value to negative peak value of current are respectively

• A. 1/200 sec, 1/ 100 sec
• B. 1/ 100 sec, 1/200 sec
• C. 200 sec, 100 sec
• D. None of these

Answer 1

Answer: (A)

1/200 sec, 1/ 100 sec

Answer 2

Time take to reach from zero to peak value $t = \frac{T}{4}$ $= \frac{1}{4\nu} = \frac{1}{4 \times 50} = \frac{1}{200}\sec$

Time take for the change from positive peak to negative peak $t' = \frac{T}{2} = \frac{1}{2\nu} = \frac{1}{2 \times 50} = \frac{1}{100}\sec$.