A 0.86kg grenade is tossed on the ground with a velocity of 6 m/s West. If the grenade explodes into 2 pieces, one that has a mass of 32kg and travels East at 10 m/s.
(A) What is the mass of the second piece
(B) What is the velocity of the second piece?

(A) 0.54 kg

(B) 15.5 m/s west

Explanation:

Mass is conserved.

M = m₁ + m₂

0.86 kg = 0.32 kg + m₂

m₂ = 0.54 kg

Momentum is conserved (take east to be positive).

Mv = m₁v₁ + m₂v₂

(0.86 kg)(-6 m/s) = (0.32 kg)(10 m/s) + (0.54 kg) v₂

v₂ = -15.5 m/s

a longitudinal wave moves energy that is to the direction of the wave’s movement. - true

the box does not move because you need to use a force greater than 300 n. you are only using 50 n. it needs to at least be 301 n for the box to move because then it is an unbalanced force and it will move the way that the greater force is pushing it. if you use only 300 n it will be a balanced force and will not move because the force you are exerting on the   box is the same as its force.

hope this !

im sorry if i went too in depth, i am going to include a link to a video on khan academy that will explain this.   hope that you like the video and that it explains more in detail to you.

that is the link.