A body covers 100 cm in first 2 seconds and 128 cm in the next four seconds moving with constant acceleration. Find the velocity of the body at the end of 8 sec ?

Explanation

In first 2 sec. `100=2u+1/2, a.4…….(1)`
In first 6 seconds : `228=6u+1/2a. 36 to (2)`
`(1) xx 3-(2) " gives "72=-12a`
`a=-6 cm//s^(2) ……(3)`
`2u=112 u=56cm//s…….(4)`
Now velocity of the body at the end of 8 sec is
`V=u+at=56-6xx8` V=8cm/s