Collision of Uniform Smooth Spheres: Finding Coefficients of Restitution

In summary, a uniform smooth sphere P with mass 3m and speed u collides with another uniform smooth sphere Q with mass m and speed 2u in the opposite direction. The resulting velocities of P and Q, measured in the direction of motion of P before the collision, are v and w respectively, with a coefficient of restitution e. The expression for v in terms of u and e is (1+e)u/4, and if e>1/3, the direction of motion of P changes after the collision. The expression for w in terms of u and e is (1-e)u/4. After colliding with P, Q then rebounds from a vertical wall with a coefficient of restitution e'. If
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Help slove pls!:(

A uniform smooth sphere P,of mass 3m, is moving in a straight line with speed u on a smooth horizontal table.Another uniform smooth sphere Q, of mass and m and having the same radius as P, moving with speed 2u in the same straight line as P but in the opposite direction to P. The sphere P collides with the sphere Q directly. The velocities of P and Q after the collision are v and w respectively, measured in the direction of motion of P before the collision. The coefficient of restitution between P and Q is e.

a) Find an expression for v in terms of u and e.
b) Show that, if the direction of motion and P is changed by the collision, then e>1/3.
c) Find an expression for w in terms of u and e.

Following the collision with P, the sphere Q then collides with and rebounds from a vertical wall which is perpendicular to the direction of motion of Q. The coefficient of restitution between Q and the wall is e'

Given that e=5/9, and that P and Q collide again in the subsequent motion,
e) Show that e'>1/9
 
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1. What is the coefficient of restitution?

The coefficient of restitution is a measure of the elasticity of a collision between two objects. It is defined as the ratio of the relative velocity of separation to the relative velocity of approach between the two objects.

2. How is the coefficient of restitution calculated?

The coefficient of restitution is calculated by dividing the relative velocity of separation by the relative velocity of approach. This can be measured experimentally by recording the velocities of the two colliding objects before and after the collision.

3. What factors affect the coefficient of restitution?

The coefficient of restitution can be affected by various factors such as the material and surface properties of the objects, the angle and speed of approach, and the presence of external forces or friction.

4. Why is the coefficient of restitution important in the study of collisions?

The coefficient of restitution is important because it allows us to understand the energy transfer and conservation during collisions. It also helps in predicting the behavior of objects after a collision, which is crucial in many practical applications such as sports, engineering, and physics experiments.

5. How can the coefficient of restitution be used to determine the type of collision?

The coefficient of restitution can be used to classify collisions as either elastic or inelastic. An elastic collision has a coefficient of restitution of 1, meaning all kinetic energy is conserved. In an inelastic collision, the coefficient of restitution is less than 1, indicating a loss of kinetic energy due to deformation or other factors.

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