Practice question
Question
A truck moving at 90km/h applies brakes and stops after 12s. If the deceleration triples after 8s, what is the total distance covered?
Explanation
Speed: 90km/h=25m/s. 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 190 m as the result, so option A is correct.