A body covers a distance of 4 m in `3^(rd)` second and 12m in `5^(th)` second. If the motion is uniformly accelerated. How far will it travel in the next 3 seconds?

Options

A. `42m`
B. `72m`
C. `12m`
D. `16m`

Answer

A

Explanation

A body covers ………………
`S_(3)rd = 6`
`U + (a)/(2)(2xx3-1) = 6`
`u+(5a)/(2) = 6` … (1)
`S_(5th) = 10`
`u + (a)/(2) (2xx5-1) = 10`
`u+(9a)/(2) = 10` ………(2)
from (a) and (2) we get
`u = 1m//s` , `a = 2m//s^(2)`
now distance travelled in next 3 second `= S_(8) - S_(5)`
`= (1xx8+(1)/(2)xx2xx8^(2)) - (1xx5+(1)/(2)xx2xx5^(2)) = 42m`