Question

A motorcycle is travelling at a constant acceleration in a straight line. When it passes by the first lamp post, it is travelling at 10ms-1. When is passes by the next lamp post which is 200m from the first lamp post, the motor cycle is travelling at 16 ms-1. What is the acceleration of the motorcycle.

Options:
A: 0.17 ms-2
B: 0.22 ms-2
C: 0.39 ms-2
D: 0.89 ms-2

What i did:
Let distance from starting point to first lamp post be x
Time taken for motorcycle to reach first lamp post would be (10/x)
Time taken to reach second lamp post would be (16/200+x)

Through a velocity time graph, acceleration would equal to rise/run which is equal to (6/((200+x/10)-(x/10)) which by solving i get acceleration = (960/2000-6x).

I still have an unknown. Help?

Answer 1

V^2 = Vo^2 + 2a*d = 16^2
10^2 + 2a*200 = 256
400a = 256-100 = 156
a = 0.39 m/s^2.