Does Altitude Affect the Height of the Bounce of a Golf Ball?





"The subject of elasticity deals with the behavior of those substances which have the property of recovering their size and shape when the forces producing deformations are removed. We find this elastic property to some extent in all solid bodies. When you push a material it gives- the material is deformed. If the force is small enough, the relative displacements of the various points in the material are proportional to the force- we say the behavior is elastic." (Holton).

"The elasticity attribute defines the elasticity value of an object. The elasticity value is a floating point number between 0 and 10. A value of 0 indicates no elasticity (i.e. a brick). A value of 10 indicates perfect elasticity (i.e. a perfect rubber ball). The elasticity of an object determines its response when dropped through gravity onto the gravity base or a gravity surface. An object having an elasticity value of 0 will not bounce at all and will remain stationary upon landing after being dropped. An object with perfect elasticity of 10 will continue to bounce indefinitely back to the place from which it was dropped. A value between 0 and 10 will cause a gradual degradation (relative to the value) of energy each time the object collides with a surface."




"In 1666, two hardwoods balls of equal size were released from rest at a certain height. It swung down and struck the other, which was hanging at rest. After impact, the ball stopped at the point of impact while the second ball swung from this point to the same height as that from which the first ball had been released. Our law of momentum conservation explains what is observed.

The scalar quantity 1/2mv(squared) has come to be called kinetic energy. The law of conservation of kinetic energy , then, is not as general as the law of conservation of momentum. If two bodies collide, the kinetic energy may or may not be conserved, depending on the type of collision. It is conserved if the colliding bodies do not crumple of smash or dent or stick together or heat up or change physically in some other way. We call any bodies that rebound without any such change perfectly elastic. We describe collisions between them as perfectly elastic collisions. In perfectly elastic collisions, both momentum and kinetic energy are conserved.

Most collisions that we witness, are not perfectly elastic and kinetic energy is not conserved. Thus, the sum of the 1/2mv(squared)'s after the collision is less than before the collision. Depending on how much kinetic energy is lost, such collisions might be called partially elastic or perfectly inelastic. The loss of kinetic energy is greatest in perfectly inelastic collisions, when the colliding bodies remain together.

Collisions between steel ball-bearings, glass marbles, hardwood balls, billiard balls, or some rubber balls(silicone rubber) are almost perfectly elastic, if the colliding bodies are not damaged in the collision. The total kinetic energy after the collision might be as much as, say, 96% of this value before the collision. Examples of true perfectly elastic collisions are found only in collisions between atoms or sub-atomic particles."(Holton).

"Elasticity number is proportional to { (elastic force) / (inertial force) } and is used in momentum transfer in general and viscoelastic flow calculations in particular. It is normally defined in the following form, where :

r = Pipe/conduit radius

mu = Viscosity

rho =Density

theta = relaxation

Pipe/conduit radius



relaxation time"

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