Question

Before colliding, the momentum of block A is -100 kg*m/, and block B is -150 kg*m/s. After, block A has a momentum -200 kg*m/s. What is the momentum of block B afterward? PLEASE HELP

Answer 1

Answer:

Momentum of block B after collision =$-50\ kg\ ms^{-1}$

Explanation:

Given

Before collision:

Momentum of block A = $p_{A1}$= $-100\ kg\ ms^{-1}$

Momentum of block B = $p_{B1}$= $-150\ kg\ ms^{-1}$

After collision:

Momentum of block A = $p_{A2}$= $-200\ kg\ ms^{-1}$

Applying law of conservation of momentum to find momentum of block B after collision $p_{B2}$.

$p_{A1}+p_{B1}=p_{A2}+p_{B2}$

Plugging in the given values and simplifying.

$-100-150=-200+p_{B2}$

$-250=-200+p_{B2}$

Adding 200 to both sides.

$200-250=-200+p_{B2}+200$

$-50=p_{B2}$

∴ $p_{B2}=-50\ kg\ ms^{-1}$

Momentum of block B after collision =$-50\ kg\ ms^{-1}$