Question

A horizontal 90kg merry-go-round is a solid disk of radius 1.50m and is started from rest by a constant horizontal force of 50.0 N applied tangentially to the the edge of the disk. the kinetic energy of the disk after 3s​

Answer 1

Answer:

276 J

Explanation:

Given,

Force (F) = 50.0N

Distance (S) = 1.50m

Time (t) = 3s

Mass (M) =F/g

               = 800/ 9.8

               = 81.63 kg

Moment of inertia (I)  =  1/2*M*(1.50)^2

                                   =  91.84kg.m^2

Torque applied (T) = F*S

                               = 50.0 * 1.50

                               = 75 N.m

Angular acceleration (a) = T/I

                                        = 75 / 91.84

                                         = 0.82 Rad/s^2

Final Angular Speed (w)  = a*t

                                          = 0.82 *3.00

                                           = 2.45 Rad/s

Kinetic energy = 1/2*I*w^2

                         = 275.6348 J