# momentum

what is momentum ?

momentum = mass x velocity

2. Conservation of momentum

Principle of conservation of momentum.

m1u1 + m2u2 = m1v1 + m2v2

Demonstration by any one suitable method.

Get a string on the string, tread a drinking straw on and attach the strings ends to 2 opposite walls ,

Across the straw lay 2 pieces of insulating tape.

Blow up a balloon and attach it to the straw using the tape.

What is the momentum of the system?

Release the balloon what happens & why?

3. Verification of the principle of conservation of momentum.

http://www.mathsphysics.com/Physics/COM.htm

Appropriate calculations

(problems involving change of mass need not be considered)

Problems involving momentum

Momentum problems

A runaway Engine of 16000kg travelling at 25m/s, collides with 5 carriages each of mass 2000kg that are at rest. If the whole train couples together and continues to roll along the track at what speed will this be at? Sticking together problem

A loaded gun fires a bullet, the 2g bullet leaves the gun at 400ms-1 if the gun is 2.5kg at what velocity does the rifle re-coil ?

You are standing in the middle of a frozen lake with zero friction. How do you reach the shore?

If you walk, you won't go anywhere. If you fall, you can't get up. Is there any plausible way to get to the shore? Assuming you have no special items like ice-picks or portable hairdryers.

walter fendt and collisions

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