Tag: bouncing balls

I’m doing a science experiment of what factors affect the distance a golf ball t…

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I’m doing a science experiment of what factors affect the distance a golf ball travels. One of my factors is the bounciness of the ball. Does this have any effect on the distance the ball will go? — EG, North Salem, NY

Yes. The bouncier the golf ball, the farther it will go after being struck by a golf club. While we normally think of a bounce as occurring when a ball hits a stationary object, it’s also a bounce when a moving object hits a stationary ball. The golf ball bounces from the golf club and the more bouncy the golf ball is, the faster and farther it will travel.

What is the difference in distance that a soccer ball will travel if the air pre…

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What is the difference in distance that a soccer ball will travel if the air pressure in the ball changes? — AB

A properly inflated soccer ball bounces well when you drop it on a hard floor because the ball stores energy by compressing the air during the bounce and the air returns this energy quite efficiently during the rebound. An under inflated soccer ball doesn’t bounce so well because it stores energy by bending its leather surface during the bounce and the leather doesn’t return energy very efficiently during the rebound. The same result holds true when you kick a ball rather than dropping it on the floor. Whether a moving ball hits a stationary surface or a stationary ball hits a moving surface, the ball is still bouncing from a surface. When you kick a ball with your foot, the ball is bouncing from your foot and a properly inflated ball will bounce more efficiently from your foot than an under inflated ball. The properly inflated ball will rebound at a higher speed and will travel farther.

What causes a dropped ball to bounce? – MK

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What causes a dropped ball to bounce? – MK

When you lift a ball off the floor, you transfer energy to it. This energy is stored in the gravitational force between the ball and the earth and is called gravitational potential energy. When you release the ball, its weight makes it accelerate downward and its gravitational potential energy gradually becomes kinetic energy, the energy of motion. When the ball hits the floor, both the ball’s bottom surface and the floor’s upper surface begin to distort and the ball’s kinetic energy becomes elastic potential energy in these two distorted surfaces. The ball accelerates upward during this process and eventually comes to a complete stop. When it does, most of the energy that was initially gravitational potential energy and later kinetic energy has become elastic potential energy in the surfaces. However, some of the original energy has been converted into thermal energy by internal frictional forces in the ball and floor. The distorted ball and floor then push apart and the ball rebounds into the air. Some or most of the elastic potential energy becomes kinetic energy in the ball, and the rising ball then converts this kinetic energy into gravitational potential energy. But the ball doesn’t reach its original height because some of its original gravitational potential energy has been converted into thermal energy during the bounce.

Does the air pressure of a basketball and the hardness of the floor surface have…

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Does the air pressure of a basketball and the hardness of the floor surface have an effect on the height of the bounce? — BB, West Unity, OH

Yes to both questions. When a basketball collides with the floor, the ball’s kinetic energy—its energy of motion—is temporarily stored as elastic potential energy in two objects: the ball and the floor. The fractions of the collision energy stored in the basketball and the floor depend on how far each of them dents—the more one dents, the larger the fraction of the collision energy it receives. How well the basketball rebounds from the floor depends on how much of the collision energy returns to the ball during the rebound. Some of the stored energy in each dented surfaces is converted to thermal energy and is lost from the bouncing process. A hardwood floor is very springy and returns its share of the collision energy efficiently. A properly inflated basketball is also very springy. Thus when a firm basketball bounces on a good hardwood floor, it bounces well. But if the basketball is underinflated, its surface bends too far so that it receives most of the collision energy and internal friction in the ball’s skin wastes most of that energy. The ball bounces weakly. And if you try to bounce the ball on a soft carpet, the carpet dents easily, receives most of the collision energy, and wastes most of it as thermal energy. Again, a weak bounce.

What effects, if any, does storage temperature have on the height of a tennis ba…

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What effects, if any, does storage temperature have on the height of a tennis ball’s bounce?

I suspect that cool storage will prolong the life of a tennis ball in an opened can. That’s because the ball’s bounciness depends on its retaining air inside its rubber shell. As the ball loses air by diffusion through the rubber, it loses its ability to bounce high. Diffusion is a thermally activated process in which the individual air molecules move between the rubber molecules and migrate through the material. At lower temperatures, the air molecules will move much more slowly through the rubber and the pressure inside the ball will stay high for a longer time.

What forces are involved when hitting the sweet spot of a baseball bat?

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What forces are involved when hitting the sweet spot of a baseball bat?

If the ball bounces from the sweet spot, the two push on one another hard. The ball slows to a stop and then reverses its direction, rebounding from the bat at high speed. The bat accelerates in the opposite direction, and begins to rotate slightly about its center of mass. This rotation is just right to keep the bat’s handle from accelerating either toward or away from the ball. That’s why the hit feels so clean and neat. The handle doesn’t accelerate. The force from the ball on the bat also doesn’t cause the bat to vibrate, because the sweet spot is a vibrational node.

When the falling ball bounced off the rising board, why did the ball go upward v…

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When the falling ball bounced off the rising board, why did the ball go upward very quickly? Because of your frame of reference?

The frame of reference from which you observe the situation doesn’t cause the rebounding ball to move quickly, but it does help you to understand why the ball rebounds so quickly. Instead of describing the ball bounce from the rising board, let’s look at the ball bouncing from a horizontally moving bat. That way, we won’t have to worry about gravity—we can pretend it doesn’t even exist for a moment. Let’s begin from the fan’s inertial frame of reference as a pitched ball heads toward a bat at home plate. As the ball approaches the bat, the bat approaches the ball. Both objects are moving, which makes things complicated. So we’ll now shift to the bat’s frame of reference for a while. In this frame of reference, the bat is stationary and the ball is approaching at high speed. (This rapid approach speed reflects the fact that the two objects are each moving toward the one another in the fan’s reference frame.) The ball now bounces from the bat. Because it approached the bat at such a high speed, the ball rebounded at a high speed, too—it heads away from the bat at high speed. Now we’ll shift back to the fan’s reference frame. The ball is still going away from the bat at high speed, but now we must notice that the bat itself is heading toward the outfield at a high speed, too. So the ball must really be heading toward the outfield fast—it’s outrunning the bat toward the outfield. And that is the case. The ball heads toward the outfield at a much higher speed than it had when it was heading toward the bat originally. In the fan’s frame of reference, there is a large transfer of energy from the bat to the ball

Why do some objects bounce off the ground (balls) whereas others would break (eg…

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Why do some objects bounce off the ground (balls) whereas others would break (eggs)?

Some objects can deform elastically, storing energy in the process, while others can’t. The surface of a rubber ball is made up of long, flexible molecules called polymers that can bend and stretch without breaking. As the ball’s surface dents during an impact, these polymer molecules move about and begin to exert forces on one another (storing energy in the process). As the ball rebounds, these molecules release their stored energy and push the ball back into the air. An egg, on the other hand, is made of hard, crystalline material that shatters during the deformation. Whole rows of atoms and molecules rip apart from one another and are unable to return. The egg doesn’t store the impact energy. Instead, it turns that energy into thermal energy. The shell just crumbles.

Why does a basketball bounce higher than a bowling ball?

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Why does a basketball bounce higher than a bowling ball?

When a ball bounces from a rigid surface, the ball’s surface distorts inward and then pops back outward. During the inward motion, the ball stores energy—pushing its surface inward takes energy. During the outward motion, the ball releases that stored energy. But not all the energy invested in the ball emerges as useful work. Some of that energy is turned into thermal energy and never reappears. A properly inflated basketball returns a good fraction of the energy it receives while other balls may not. In fact, a bowling ball bounces pretty well from a hard surface such as cement. But when it hits a softer surface such as wood, the wood receives much of its energy and wastes that energy as thermal energy.