Question

How to calculate momentum after collision?

Answer 1

Seem like physics to me, consider this article: http://hyperphysics.phy-astr.gsu.edu/hbase/colsta.html

Answer 2

(Total) momentum is the sum of the product of the velocity of moving objects and the mass. They should be equal before and after impact/collisions.
\[momentum = \sum_{i=1}^{n} m _{i} v _{i}\]

Answer 3

so what do i need to divide or multiply or + or - ?

Answer 4

the equations are too complicated for me.. lol.

Answer 5

What level physics are you at?

Answer 6

like it's easier for me to understand something if i know what to x, divide, + or - (:

Answer 7

Integrated Physics.

Answer 8

The formula above means add up the product of the mass of all moving objects by their velocities.

Velocity being a vector, so the sign is important, depending on the direction of travel.

Do you have an example you'd like to solve?

Answer 9

yes hold up

Answer 10

A 1.0 kg ball with a velocity of 5 m/sec hits another 1.0 kg ball that is stationary. What is the momentum of each ball after and before collision?

Answer 11

The momentum before collision is the sum of mv, i.e.
momentum = 1*5 + 1*0 = 5 kg-m-s-1
As I mentioned earlier, momentum before and after impact are the same.
So total momentum after impact is also 5 kg-m-s-1.

Answer 12

thank you!!

Answer 13

Sorry, the question asked for each ball.
So before impact, the moving ball has a momentum of 5*1 = 5.
The stationary ball has a momentum of 5*0 = 0
After impact, the velocities differ according to the type of collision.

If the collision is elastic (like a billiard ball hitting another), the the relative velocity between the two balls remain the same as before and after impact, so the previously moving ball will bounce backwards, and the stationary ball will move forward.

If the collision is inelastic (like a piece of putty hitting another), both balls will move with a common velocity, say v, such that the total momentum is conserved.
m1u1 + m2u2 = (m1+m2)v
where m1,m2 are masses
u1,u2 are velocities before impact, and
v is the common velocity after an inelastic impact.

For our case,
1*5 + 1*0 = (1+1)v
solving for v:
v=5/(1+1) = 2.5 kg-m/s.

Answer 14

Sorry, the above velocity v should have a unit of m/s.
and the momentum of each ball after impact is 1*2.5 = 2.5 kg-m/s.