Practice question
Question
A car moving at 35m/s decelerates uniformly to rest over 87.5m. What is the deceleration?
Explanation
Use v2=v02+2ax. Here, v=0, v0=35m/s, x=87.5m. As per NCERT Chapter 3, equations v=u+at, s=ut+½at², v²=u²+2as describe uniformly accelerated motion. Applying correct signs and units gives 7 m/s² as the result, so option B is correct.