Adding to Nicael's and Dzuris' excellent answers, I thought it's worthwhile to go into greater detail about exactly why some elastic objects do not bounce in a place where rubber balls do. Note that all considerations here are fairly symmetrical: You can often exchange "floor" and "ball", or consider two balls. Which one is in danger of being plastically deformed is interchangeable; both must undergo exclusively elastic deformation.

A good example are steel balls. Watching Newton's Cradle makes it clear that steel is — somewhat counter-intuitively — elastic; very little energy is lost on each bounce. Nonetheless steel balls don't bounce well in places where super balls or ping-pong balls do, for example on tarmac or the hardwood floor of your living room.

The reason is that the "coefficient of elasticity" of steel is very high, meaning that you need a lot of force to deform it. Long before the force is reached which would meaningfully deform the steel, you have a dent in the hardwood or in the tarmac. It's also important that a massive steel ball is heavy, generating the high forces which deform the ground. I would think (although I have never tried) that a massive aluminum ball would bounce of surfaces like concrete where a steel ball would not, just because the generated forces don't damage the ground that much.

Generally a ball will bounce if the material is elastic, and if the forces acting on the ground surface stay smaller than needed to plastically deform the ground. That is influenced by the following factors (in addition to having an elastic ball):

• A low coefficient of elasticity of the ball (i.e. a "soft" ball), increasing the impact surface and hence lowering the force per area on the ground.

• A low density (a ping-pong ball will bounce off of many surfaces where even a super ball will not), again leading to lower overall impact forces.

• A hard floor surface, hard enough to withstand the impact forces: A small steel ball may bounce off of a marble or granite floor but not one made of chalk.

• Low impact velocity. A steel ball may bounce efficiently off of a marble surface when dropped from a few feet, but not when shot at it with a gun.

Adding to Nicael's and Dzuris' excellent answers, I thought it's worthwhile to go into greater detail about exactly why some elastic objects do not bounce in a place where rubber balls do. Note that all considerations here are fairly symmetrical: You can often exchange "floor" and "ball", or consider two balls. Which one is in danger of being plastically deformed is interchangeable; both must undergo exclusively elastic deformation.

A good example are steel balls. Watching Newton's Cradle makes it clear that steel is — somewhat counter-intuitively — elastic; very little energy is lost on each bounce. Nonetheless steel balls don't bounce well in places where super balls or ping-pong balls do, for example on tarmac or the hardwood floor of your living room.

The reason is that the "coefficient of elasticity" of steel is very high, meaning that you need a lot of force to elastically deform it. Long before the force is reached which would meaningfully deform the steel, you have a permanent dent in the hardwood or in the tarmac: the ball's energy has been used to damage the floor instead of elastically compressing the ball. It's important that a massive steel ball is heavy, generating the high forces which damage the ground. I would think (although I have never tried) that a massive aluminum ball would bounce of surfaces like concrete where a steel ball would not, just because the generated forces don't damage the ground that much.

Generally a ball will bounce if the material is elastic, and if the forces acting on the ground surface stay smaller than needed to plastically deform — i.e., damage — the ground. That is influenced by the following factors (in addition to having an elastic ball):

• A low coefficient of elasticity of the ball (i.e. a "soft" ball), increasing the impact surface and hence lowering the force per area on the ground.

• A low density (a ping-pong ball will bounce off of many surfaces where even a super ball will not), again leading to lower overall impact forces.

• A hard floor surface, hard enough to withstand the impact forces: A small steel ball may bounce off of a marble or granite floor but not one made of chalk.

• Low impact velocity. A steel ball may bounce efficiently off of a marble surface when dropped from a few feet, but not when shot at it with a gun.