Question

Calculate the value of the angular acceleration of the motor using the given data: J = 81 kg-m^2, load torque = 74 N-m, motor torque = 89 N-m.

(a) .195 rad/s^2

(b) .182 rad/s^2

(c) .183 rad/s^2

(d) .185 rad/s^2

I have been asked this question during a job interview.

I want to ask this question from Modified Speed Torque Characteristics of DC Series Motors topic in chapter Characteristics of DC & AC Motors of Electric Drives

Answer 1

Right choice is (d) .185 rad/s^2

To explain: Using the dynamic equation of motor J×(angular acceleration) = Motor torque – Load torque: 81×(angular acceleration) = 89-74=15, angular acceleration=.185 rad/s^2.