1.

The wheel of a motor rotates with a constant acceleration of `4" rad s"^(-1)`. If the wheel starts form rest, how many revolutions will it make in the first 20 second?

Answer» The angular displacement in the first 20 s is given by
`theta=omega_(0)t+(1)/(2)alphat^(2)=(1)/(2)("4 rads"^(-2)(20s)^(2))`
`(because "Angular velocity" omega=0)`
= 800 rad
As, the wheel turns by `2pi` radian in each revolution, the number of revolutions in 20 s is
`N=(theta)/(2pi)=(800)/(2pi)=128`


Discussion

No Comment Found

Related InterviewSolutions