Question

An object moving with constant acceleration changes its speed from 20 m/s to 60 m/s in 2.0 s. What is the acceleration? (b) How far did it move in this time?

Answer 1

acceleration, a =
`20 m/s^(2)`

distance, d = 80 m

Given:

Initial velocity of object, v = 20 m/s

Final velocity of object, v' = 60 m/s

Time interval,
`\Delta t = 2.0 s`

Solution:

(a) Acceleration is the rate at which velocity changes and constant acceleration is when the velocity changes by equal amount in equal intervals of time.

Thus

acceleration, a =
`(v' - v)/(\Delta t)`

a =
`(60 - 20)/(2.0) = 20 m/s^(2)`

(b) Now, the distance covered is given by:

`d = vt + (1)/(2)at^(2)`

`d = 20* 2.0 + (1)/(2)20* 2^(2) = 80 m`