A car starts from rest and after 7 seconds it is moving at 42 m/s. What is the car's average acceleration?

1 Answer
Feb 21, 2016

#a_{avg}=6ms^-2#

Explanation:

We'll use a simple kinematic equation to solve this.
#v=v_o+at#

Here, given that #v=42ms^-1#, #s=7s# and that it started from rest so #v_o=0ms^-1#, we get
#42=0+a*7=cancel{42}^6/cancel{7}^1=a#

So, that's how we got acceleration.