Answer to Question #315581 in Mechanics | Relativity for Aune

Question

Suppose we experiment with an Atwood Machine consisting of two masses m

and 2m connected by an inextensible non-slip string running over a pulley of

radius a and mass 4m, as shown below.

) Briefly discuss why no work is done by the forces of constraint. (5)

(d) What is the total energy of the system? (2)

(e) Find the acceleration dv/dt of the blocks.

Answer 1

$a=g\frac{m_2-m_1}{m_2+m_1}=3.27~\frac m{s^2},$

$I=2mr^2,$

$\omega=\frac ar,$

$E=\frac{I\omega^2}2=10.7mr^2~J.$