Question

Describe the forces acting on the rock,and use the concept of forces to explain why it stays on top of the boulder

Answer 1

We are given the following situation:

We are given that a rock is on equilibrium on top of a boulder. The forces acting on the boulder are the weight of the boulder, given by:

`W=mg`

Where:

`\begin{gathered} W=\text{ weight} \\ m=\text{ mass} \\ g=\text{ acceleration of gravity} \end{gathered}`

And the normal force that acts in a direction perpendicular to the surface of contact between the rock and the boulder.

Since the rock stays on top this means that the net force on the boulder is zero. This means that the sum of all the forces acting on the rock is zero.