Why is the sum of the forces on colliding objects zero? (momentum is conserved)
2006-12-10 09:04:00 · 2 answers · asked by coolguy0603 1 in Science & Mathematics ➔ Physics
If momentum is conserved and if there are two objects...
Δp1 = Δp2
Force is also Δp/s
so the time the objects are affecting each other are the same for both objects so F1 = F2
2006-12-10 09:12:35 · answer #1 · answered by feanor 7 · 0⤊ 0⤋
Force and mometum are vector quantities, which means that they have magnitude and direction. Assuming no energy loss, due to heat sound or deformation, during the collision all momentum should be conserved. Use the break in a game of pool as an example.
When the cue is stuck and is moving toward the rack, it has a direction and a certain amount of momentum. When the cue strickes the rack, the balls scatter. If you were to take the sum of the momentum of each ball as well as the vectors of the direction that each ball took, they would equal that of the initial direction and momentum of the cue.
If p is the total mometum in each case,
p(cue) = p(balls)
Algebraically move move all terms to the left side and you get:
p(cue) - p(balls) = 0
Therefore, the sum of the mometums is zero.
2006-12-10 17:14:32 · answer #2 · answered by Mr. Payne 3 · 0⤊ 0⤋