Summary A2 Physics - Further Mechanics

Chapter 5 – Further
Mechanics




Kim Sohoon

, Date


ENERGY IN COLLISION

1. ELASTIC COLLISION
A. Definition
i. Elastic collision is a collision in which there is no net loss in kinetic energy in the
system
ii. Elastic collision is in which kinetic energy and momentum is conserved
B. Explanations
i. Momentum before and after must be same
ii. Kinetic energy before and after must be same
iii. Newton’s Cradle is an example that has nearly perfect elastic collision between
metal balls
iv. However, tiny amount of energy is lost due to sound and heat generated when
they collide
C. Equation

i. m A v Ai +mB v Bi=m A v Af + mB v Bf
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ii. m v2 + m v2 = m v2 + m v2
2 A Ai 2 B Bi 2 A Af 2 B Bf


2. INELASTIC COLLISIONS
A. Definition
i. Inelastic collision is when momentum is conserved, but kinetic energy is not
conserved
ii. Inelastic collision is when momentum before and after is same, but there is loss
in kinetic energy
B. Explanation
i. Energy is lost to hear, sound or in other form after they collide
ii. Example of inelastic collision can be found everywhere




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