- #1

Clara Chung

- 304

- 14

## Homework Statement

A point like body with mass m

_{1}is placed on top of a table, that can freely move on wheels with respect to the ground. There is a static friction coefficient of u=0.3 between the body and the table. If the body is subject to the gravitational acceleration g, what is the maximal horizontal acceleration that the table can have, before the body start moving with respect to it?

Consider now the case of where the body is attached to a horizontal massless and frictionless rope. This rope turns around a frictionless pulley placed at the side of the table, and below it hangs another body with mass m

_{2}. Calculate the forces acting on the system in the reference frame of the table. Calculate the maximum acceleration (in the direction opposite to m

_{2}) that the table can stand before the masses start to move, neglecting the change in the angle of the string supporting m

_{2}.

## Homework Equations

The answer of the first part is um

_{1}. The answer of the second part is a=(m

_{2}-um

_{1})/(m

_{1}+m

_{2}).

## The Attempt at a Solution

I have no idea how to do both parts of the questions. I want to solve the first part first. I attempted to solve the question by equating um

_{1}g = m

_{table}a

_{table}, because the friction force is equal to the force m

_{1}acting on the table. Without the mass of the table, how can I know its acceleration?