A Car Starts From Rest And Accelerates Uniformly To Reach A Speed Of 21 M/S In 7 Seconds. What Was The Speed Of Object After 2 Seconds?

A car starts from rest and accelerates uniformly to reach a speed of 21 m/s in 7 seconds. What was the speed of object after 2 seconds?

 

Good Day

Problem:

A car starts from rest and accelerates uniformly to reach a speed of 21 m/s in 7 seconds. What was the speed of object after 2 seconds?

Given Data:

Vi (initial velocity) = 0 m/s

Vf (final velocity)  = 21 m/s

t (time)    = 7 seconds

a (acceleration ) = ? unknown

Solution:

First:

We have to find the acceleration using the formula a = Vf-Vi / t

a = Vf-Vi / t

  = 21 m/s - 0 m/s / 7 s

  = 21 m/s / 7 s

  = 3 m/s^2

Second:

We can the final velocity of an object in 2 seconds using the formula

Vf = at + Vi

    = 3 m/s^2 × 2 seconds + 0 m/s

    = 6 m/s + 0 m/s

    = 6 m/s

Answer

The velocity in 2 seconds is 6 m/s

Hope it helps...=)