Question

Calculate the value of the angular acceleration of the Heavy duty crane using the given data: J = 5 kg-m^2, load torque = 30 N-m, motor torque = 80 N-m.

(a) 10 rad/s^2

(b) 20 rad/s^2

(c) 30 rad/s^2

(d) 50 rad/s^2

The question was posed to me in an interview.

This key question is from Motors Rating and Heating topic in division Rating and Heating of Motors of Electric Drives

Answer 1

The correct answer is (a) 10 rad/s^2

Easiest explanation: Using the dynamic equation of motor J×(angular acceleration) = Motor torque – Load torque: 5×(angular acceleration) = 80-30=50, angular acceleration=10 rad/s^2.