Question

A train moves from rest to a speed of 25 m/s in 30.0 seconds. What is the acceleration?

Answer 1

`a = 0.83\ m/s^2`

Step-by-step explanation:

Uniform Acceleration

When an object changes its velocity at the same rate, the acceleration is constant.

The relation between the initial and final speeds is:

`v_f=v_o+a.t`

Where:

vf = Final speed

vo = Initial speed

a = Constant acceleration

t = Elapsed time

It's known a train moves from rest (vo=0) to a speed of vf=25 m/s in t=30 seconds. It's required to calculate the acceleration.

Solving for a:

`\displaystyle a=(v_f-v_o)/(t)`

Substituting:

`\displaystyle a=(25-0)/(30)`

`\boxed{a = 0.83\ m/s^2}`