A particle of mass `m` moving with a velocity `u` makes an elastic one-dimensional collision with a stationary particle of mass `m` establishing a contact with it for extermely small time. `T`. Their force of contact increases from zero to `F_0` linearly in time `T//4`, remains constant for a further time `T//2` and decreases linearly from `F_0` to zero in further time `T//4` as shown. The magnitude possessed by `F_0` is.
.

Options

A. `(m u)/T`
B. `(2m u)/(T)`
C. `(4m u)/(3 T)`
D. `(3 m u)/(4T)`

Answer

C

Explanation

Impulse on particle m = Area under `F - t "curve" = (F_(0)(T + T/2))/(2) = m (0 - u)`
`:. F_(0) = (4 m u)/(3T)`.