Its velocity and acceleration vectors are pointing the same direction, meaning upward movement. The ball is less deformed than the maximum deformation stage, and due to its elasticity, it is now pushing against the surface with a force greater than its own weight.
This is what will cause the ball to bounce upward. At zero contact rebound, the ball is no longer deformed and is barely touching the surface, essentially only at one point. Velocity is moving the ball upward, but at this point, acceleration switches to oppose the velocity vector. This is because there is no longer any force from the elasticity of the ball pushing on the surface, giving it an upward acceleration.
Acceleration due to gravity, which pulls downward, will now be the only force acting on the ball in a perfect system. At full rebound, the ball has left the surface, and its velocity vector still points upward, though shrinking steadily due to the acceleration or deceleration due to gravity. Following this step, the ball with reach peak at a new step, one where its velocity vector is zero, and the only force acting on it is gravity.
The case of the bouncing ball above was simplified to remove any other forces like air resistance, imperfect elasticity, spin, friction, and the force from an initial throw, among others. All this means that bouncing ball physics gets more complicated from here. When balls have any spin, as they usually do when thrown, and when the surface they hit isn't frictionless, the spin of the ball reverses from before to after impact.
This is due to the force of friction. Assuming 2-dimensions for theory's sake, you can observe the reaction below. As the ball impacts with a spin in one direction, the friction force F counteracts the spin of the ball. Or rather, the friction force is always opposite the direction of the slip velocity between the spinning ball and the surface. Since the friction force is opposite of the ball's spin, it torques the ball in the other direction.
It also causes the path of the ball's bounce to skew in the direction of the friction force. In simplified terms, when a ball spins in one direction when it hits a wall, the friction between the ball and the wall overcomes the spin so much that it reverses its spin direction. If you rolled this material into a ball, it would bounce just a little. He said what rubber and this material have in common is that they are both polymers.
You can think of polymers being like a bowl of cooked spaghetti. Each noodle is a chain of different chemical parts.
Sometimes those spaghetti noodles are tangled up and tighter. Other times they are less tangled. The thing about polymers is that they can do different things, depending on their shape and how they are put together. When a rubber ball hits something, it absorbs energy and releases energy really fast, Zheng said.
If you throw the ball, the energy might come from your hands. If you drop it, gravity gives the ball energy. And when the ball moving, it carries the energy in the form of kinetic energy. When it hits something, it stops, and the kinetic energy is stored inside the ball as internal energy. Then it can quickly convert the internal energy back into kinetic energy which allows the ball to bounce back. We loved seeing them in action! Science Sparks Wild Sparks Enterprises Ltd are not liable for the actions of activity of any person who uses the information in this resource or in any of the suggested further resources.
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A Chair for Goldilocks ».
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