A body is moving with a uniform acceleration coverss `40 m` in the first 4 s and `120 m` in next 4s. Its initial velocity and acceleration are

Options

A. `0, 5 m//s^(2)`
B. `4 m//s, 5m//s^(2)`
C. `4 m//s, 0`
D. `4 m//s, 5 m//s^(2)`

Answer

A

Explanation

`A` to `B: 40=uxx4+1/2axx4^(4)`
`40=4u+8a …(i)`
`A` to `C: 40+120=uxx8+1/2axx8^(2)`
`160=8u+32a …(ii)`
Solving (i) and (ii), we get
`u=0, a=5 m//s^(2)`