Question

A ball starts at rest and rolls down an inclined plane. The ball reaches 7.5 m/s in 3 seconds. What is the acceleration?

Answer 1

Answer:

$a=2.5\ m/s^2$

Explanation:

Motion With Constant Acceleration

It's a type of motion in which the velocity of an object changes uniformly over time.

The equation that describes the change of velocities is:

$v_f=v_o+at$

Where:

a   = acceleration

vo = initial speed

vf  = final speed

t    = time

Solving the equation for a:

$\displaystyle a=\frac{v_f-v_o}{t}$

The ball starts at rest (vo=0) and rolls down an inclined plane that makes it reach a speed of vf=7.5 m/s in t=3 seconds.

The acceleration is:

$\displaystyle a=\frac{7.5-0}{3}$

$\boxed{a=2.5\ m/s^2}$