A body travelling with uniform acceleration crosses two point `A` and `B` with velocities `20 m s^-1` and `30 m s^-1` respectively. The speed of the body at the mid-point of `A` and `B` is.

Options

A. `25.5 ms^(-1)`
B. `25ms^(-1)`
C. `24ms^(-1)`
D. `10sqrt6 ms^(-1)`

Answer

A

Explanation

A particle moving with nonzero velocity cannot have zero speed.
`v = sqrt((v_1^2 + v_2^2)/(2)) = sqrt(((20)^2 + (30)^2 )/(2) )`
` v = sqrt650 = 25.5 m//s`