An alternator produces an emf given by volts

PHYSICS · Subjective · CBSE · Physics · Alternating Current · Alternating Current

Problem

An alternator produces an emf given by

\varepsilon(t)=170\,\sin(100\pi t)

volts, where

t

is in seconds. (i) Calculate the frequency and the period of the emf. (ii) Determine the smallest positive time after

t=0

when the emf first reaches

+85\,\text{V}

. (iii) Calculate the time interval between this instant and the next instant when the emf attains its first negative maximum value.