A bomb at rest explodes into three parts of the same mass. The linear momenta of the two parts are `-2phati` and `p hati` Calculate the magnitude of momentum of third part .

Answer

`psqrt5` .

Explanation

Here, `vec(p_1) = -2 phati = 2p` along negative X-axis
`vec(p_(2)) = p hat j = p` along Y-axis
Resultant momentum of the two parts
`p = sqrt(p_(1)^(2) + p_(2)^(2)) = sqrt((2 p)^(2) + p^(2)) = p sqrt5`
As the bomb was initially at rest final momentum of all the three parts must be zero.
`vec(p_(3)) + vec(p) = 0 `
`vec(p_(3)) = - vec(p)= - p sqrt(5) = p sqrt(5)` (in magnitude).