In Physics (Class 11, Work, Energy and Power), the Coefficient of Restitution (e) is a number that indicates how much kinetic energy is retained after two objects collide. It essentially measures the 'bounciness' of a collision.
Symbol: e.
Formula: Relative velocity of separation / Relative velocity of approach.
Range: 0 ≤ e ≤ 1.
e = 1: Perfectly elastic collision.
e = 0: Perfectly inelastic collision (objects stick together).
The Coefficient of Restitution (e) is defined as the ratio of the relative velocity of separation after collision to the relative velocity of approach before collision.
Formula: e = (v₂ - v₁) / (u₁ - u₂) Where:
The value of 'e' always lies between 0 and 1.
1. Perfectly Elastic Collision (e = 1)
2. Perfectly Inelastic Collision (e = 0)
3. Partially Elastic/Inelastic Collision (0 < e < 1)
It is the ratio of the relative velocity of separation after a collision to the relative velocity of approach before the collision. It measures how elastic a collision is.
For a perfectly elastic collision, the coefficient of restitution (e) is exactly 1.
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