An object with a mass of 2 kg2kg is traveling in a circular path of a radius of 7 m7m. If the object's angular velocity changes from 7 Hz7Hz to 9 Hz9Hz in 3 s3s, what torque was applied to the object?

1 Answer
Nov 1, 2017

410.7 Nm

Explanation:

"Torque = Rate of change of Angular Momentum"Torque = Rate of change of Angular Momentum

= (L_f - L_i) / t=LfLit

= (I ω_f - I ω_i) / t ………[∵ Angular Momentum = I ω]

= (I(ω_f - ω_i))/t

= (2piI(f_f - f_i))/t …………[∵ ω = 2pif]

=(2pixxmr^2(f_f - f_i))/t

=(2xx22/7 × 2kg × (7 m)^2 × (9Hz - 7Hz))/(3s)

=410.7 Nm