# Physics

posted by .

A ball of mass 0.640 kg moving east (+x direction) with a speed of 3.00 m/s collides head-on with a 0.740 kg ball at rest. If the collision is perfectly elastic, what will be the speed and direction of each ball after the collision?

• Physics -

Your question and those of your classmates keep using the word "prefectly". A reaction is either elastic, or not elastic. One cant be imperfectly elastic, nor perfectly elastic.

momentum:
.640*3= .640V1 + .740V2

energy:
1/2 .640*9=1/2 .640 V1^2+ 1/2 .740 V2^2

use the first equation to solve for V1 in terms of all else, then put that expression into the second equation, and have fun expanding it and collecting the terms. You will have a quadratic, use the quadratic equation to solve it.

• Physics -

actually they can be inelastic.....

## Similar Questions

1. ### U-Phys

A 0.060kg tennis ball, moving with a speed of 5.8m/s, has a head-on collision with a 0.10kg ball initially moving in the same direction at a speed of 2.8m/s. Assuming a perfectly elastic collision, determine the speed of each ball …
2. ### PHYSICS

A 0.445 kg ice puck, moving east with a speed of 2.82 m/s, has a head-on collision with a 0.918 kg puck initially at rest. Assuming a perfectly elastic collision, what will be the speed and direction of each object after the collision?
3. ### Physics

A ball of mass 0.640 kg moving east (+x direction) with a speed of 3.10 m/s collides head-on with a 0.780 kg ball at rest. If the collision is perfectly elastic, what will be the speed and direction of each ball after the collision?
4. ### Physics

A 120 g ball moving to the right at 4.2 m/s catches up and collides with a 450 g ball that is moving to the right at 1.2 m/s. If the collision is perfectly elastic, what are the speed and direction of each ball after the collision?
5. ### physics

A softball of mass 0.220 kg that is moving with a speed of 5.5 m/s (in the positive direction) collides head-on and elastically with another ball initially at rest. Afterward it is found that the incoming ball has bounced backward …
6. ### physics

A 0.060 kg tennis ball, moving with a speed 2.50 m/s, collides head on with a 0.090kg ball initially moving away from it at a speed of 1.15 m/s. Assuming a perfectly elastic collision, what are the speed and direction of each ball …
7. ### phy

A ball of mass 0.540 kg moving east (+x direction) with a speed of 3.30 m/s collides head-on with a 0.740 kg ball at rest. If the collision is perfectly elastic, what will be the speed and direction of each ball after the collision?
8. ### Physics

‎1. A 3kg body moving towards the east with a speed of 5 m/s collides with a 2kg ball originally at rest. After the collision the 3kg body moves in a direction of 25 degrees N of E. If the collision is perfectly elastic Find: …
9. ### physics collision

A 0.060 kg tennis ball, moving with a speed of 7.00 m/s has a head-on collision with a 0.086 kg ball initially moving in the same direction at a speed of 3.10 m/s. Assume a perfectly elastic collision and take the initial direction …
10. ### physics

A ball of mass 0.440 kg moving east (+x direction) with a speed of 3.80 m/s collides head-on with a 0.600 kg ball at rest. If the collision is perfectly elastic, what will be the speed and direction of each ball after the collision?

More Similar Questions