Question

24. The rate of change of the angular velocity with respect to defines angular acceleration. A. Speed B. Frequency C. Distance D. Time E. Gravity​

Answer 1

D. Time is the correct answer.

Answer 2

Answer:

) We shall use ω=ω

0

+αt

ω

0

= initial anugular speed in rad/s

=2π× angular speed in rev/s

=

60s/min

2π×angular speed in rev/min

=

60

2π×1200

rad/s

=40πrad/s

Similarly ω= final angular speed in rad/s

=

60

2π×3120

rad/s

=2π×52rad/s

=104πrad/s

∴ Angular acceleration

α=

t

ω−ω

0

=4πrad/s

2

The angular acceleration of the engine =4πrad/s

2

(ii) The angular displacement in time t is given by

θ=ω

0

t+

2

1

αt

2

=(40π×16+

2

1

×4π×16

2

) rad

=(640π+512π)rad

=1152πrad

Number of revolutions =

2π

1152π

=576