A runner starts from rest and accelerates at 1.5m/s2 for 4s, then maintains constant speed. What is the average speed ov
Acceleration: v=1.5⋅4=6m/s, x1=12⋅1.5⋅(4)2=12m. 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 5 m/s as the result, so option B is correct.
Ref: NCERT Class 11 Physics > Chapter 3: Motion in a Straight Line > Topic: Uniform Acceleration and Graphical Analysis