The wheel of a motor, accelerated uniformly from rest, rotates through 2.5 radian during the first second. Find the angle rotated during the next second.

Explanation

As the angular acceleration is constant, we have
`theta=omega_0t+1/2alphat^2=1/2alphat^2`.
`Thus `2.5rad=1/2alpha(1s)^2`
`alpha=5rad/s^2`
or `alpha=5rad/s^2`
the angle rotated during the first two seconds is
`=1/2xx(5rad/s^2)(2s)62=10rad`.
Thus the angle rotated during the 2nd second is
`10rad-2.5rad=7.5rad.`