Posted by **tina** on Wednesday, February 25, 2009 at 11:23pm.

two different masses have equal, non zero kinetic energies. the momentum of the smaller mass is?

what is the magnitude of momentum of a 0.140 baseball traveling at 45.0m/s?

a 2.00g bullet hits and becomes embedded in 5.00 kg wood block which is hanging from a 1.60m long string. this causes the block to swing through an arc of 5.50(degrees). what was the speed of the bulletbefore it hit the block ?

a 14000kg boxcar is coasting at 1.50m/d along a horizontal track when it hits and couples with a stationary 10000kg boxcar. what is the speed of the cars after the collision?

- physics -
**drwls**, Thursday, February 26, 2009 at 2:16am
Let m be the smaller mass and v be the velocity of that mass. Let M be the larger mass and V be its velocity.

Because the energies are equal,

m v^2 = M V^2

(mv)^2/m = (MV)^2/M

mv/(MV) = sqrt (m/M) < 1

(since m/M < 1)

Therefore the smaller mass also has less momentum.

========================

You left out the dimensions of the mass of the baseball. I assume it is kg

Momentum magnitude is mass x velocity. You should know that. Do the calculation. Don't forget the units, which should be kg m/s

Your last two questions require you to apply the law of conservation of momentum

## Answer This Question

## Related Questions

- physics - two different masses have equal, non zero kinetic energies. the ...
- physics - Identical forces act for the same length of time on two different ...
- physics - A gun is fired vertically into a 1.55 kg block of wood at rest ...
- Physics Momentum - 1) Two 1 kg balls move away from each other, one traveling 5 ...
- physics - Which one of the following statements is true for two bodies having ...
- PHYSICS - A light spring (k= 130 N/m) is compressed 15 cm between two masses (1....
- physics - a 2.5 kg rifle fires a 20 g bullet at 400 m/s. What is the magnitude ...
- PHYSICS - PLEASE HELP - Part A: A cardinal (Richmondena cardinalis) of mass 4.50...
- PHYSICS - PLEASE HELP - Part A: A cardinal (Richmondena cardinalis) of mass 4.50...
- Physics: Collison/Momentum Problem - A 15 kg mass, moving east at 5 m/s, ...

More Related Questions