Question

A student holding a rod by the center
subjects it to a torque of 1.4 N-m about an
axis perpendicular to the rod, turning it
through 1.3 radians in .75s. When the
student holds the rod by the end and
applies the same torque to the rod, through
how many radians will the rod turn in 1
second?

Answer 1

T = I * alpha

T constant so

I1 alpha1 = I2 alpha2

You know the diff between I's too

Ie. Use Parallel axes theorem for rod or just look it up or derive it.

Answer 2

oh, and alpha comes from the basic law of motion for rotation -- rotational equivalent of:
x = ut + 1/2 a t^2

ie alpha = (2 theta) / (t ^2)

assumes const alpha.....

Answer 3

how do you know that initial angular velocity is 0?