Torque Problem set

1. Nov 15, 2011

Whowhat2

N) Cody sits on a frictionless swivel chair(as in the lecture hall). He rests two 5lb weights,which can be approximated as point masses, on his lap (near the axis of rotation) and pushes off to spin the assembly with a rotation speed of 1 revolution per second. Approximate the person and chair combination as a cylinder 35cm in diameter, 1 meter in length with a uniform density of 1 g/cm3. What is the total kinetic energy in this rotating system?
O) He then extends his arms to hold the 5lb weights,1 meter to his left and right as in the demo. Assume that the distribution of masses in the person and chair combination does not change by extending the arms (ie massless arms), only the position of the two 5lb point masses. What is the time for 1 rotation with this distribution of masses.
P) Make a sketch and indicate the angular vector. Indicate the magnitude in rad/sec.
Q) How much tension in the arms here leads to this centripetal acceleration of the masses. R) Show that the total kinetic energy in this rotating system is the same as in N).

2. Nov 15, 2011

LawrenceC

We cannot provide any assistance until we see what effort you've applied towards the solution of the problem.