Angular acceleration spin-dry cycle

[brncsfns5621]

Just checking to see fi I did the math right:

During the spin-dry cycle of a wash, the motor slows down from 95 rad/s to 30 rad/s while turning the drum through an angle of 402 radians. What is the magnitude of the angular acceleration of the motor?

= 1/2(Wo + W)t
402 = 1/2(95 + 30)t
402 = 62.5t
6.4 = t

ang. accel. = W - Wo / t - to
= 30 - 95 / 6.4
= 10 rad/s^2

 

[civil_dude]

Looks good to me.

 

[kyle8921]

Great job on your calculations! It looks like you have correctly calculated the magnitude of the angular acceleration of the motor during the spin-dry cycle. Angular acceleration is defined as the rate of change of angular velocity, and is measured in radians per second squared. In this case, the motor is slowing down, which means its angular velocity is decreasing. The negative sign in your calculation indicates that the acceleration is in the opposite direction of the initial velocity. Keep up the good work!