Question

a biker starts a race and crosses the half line in 3 second with speed 54km/h and after that he increases his speed uniformally at a rate 7.5m/s² and completed the race in 5 second.choose the correct option - 1.Acceleration in the first half is 5 m/s².2.He finished the rae with speed 108km/h.3acceleration in the second half of the race is 12.5m/s².NOTE MORE THAN ONE OPTION CAN BE CORRECT​

Answer 1

Answer:

b is the correct answer

Explanation:

Solution:-

s=54×1000/3600= 15 ms-1

t=3s

d=15×3=45m

he increases his speed uniformly at a rate 7.5Ms-2

u=15m/s

a=7.5m/s2

t=2s

v=u+at

v=15+7.5×2

=30ms-1

=30×3600/1000 =108km/h