A solid disk with a radius of #12 m# and mass of #8 kg# is rotating on a frictionless surface. If #640 W# of power is used to increase the disk's rate of rotation, what torque is applied when the disk is rotating at #16 Hz#?

1 Answer
May 9, 2017

Answer:

The torque is #=6.4Nm#

Explanation:

Mass of disc #=8kg#

Radius of disc #=12m#

The power is related to the torque by the equation

#P=tau *omega#

#P=640W#

Frequency of rotation is #f=16Hz#

#omega=f*2pi#

angular velocity, #omega=16*2pi rads^-1#

torque, #tau=P/omega#

#=640/(32pi)=6.4Nm#