Question

A person swings a rock around on a string, causing it to sweep out in a circle of radius 0.90 m. If the rock travels at a constant speed of 5.1 m/s, what acceleration does it experience?

Answer 1

Given:

The radius of the circle, r=0.90 m

The constant speed of the rock, v=5.1 m/s

To find:

The acceleration of the rock.

Explanation:

The acceleration acting on the rock in this case is called centripetal acceleration. The centripetal acceleration changes the direction of the rock at every point on its path keeping the rock in its circular path.

The acceleration of the rock is given by,

$a=\frac{v^2}{r}$

On substituting the known values,

$\begin{gathered} a=\frac{5.1^2}{0.90} \\ =28.9\text{ m/s}^2 \end{gathered}$

Final answer:

The acceleration experienced by the rock is 28.9 m/s²