Forces Acting on a Ball: Identifying the Unknowns

AI Thread Summary
The discussion focuses on identifying the forces acting on a ball, including weight, normal force, kinetic friction, static friction, tension, and drag. It confirms the presence of weight and normal force while questioning the roles of static friction, drag, and kinetic friction. Static friction occurs when two objects attempt to slide without moving, while kinetic friction applies when they are sliding. Tension is defined as the force exerted by a rope or similar object, and drag is the resistance encountered when an object moves through a fluid. The conversation raises a specific question about the normal force acting on a tennis ball in contact with air, highlighting the complexities of these forces.
kristibella
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Identify the forces on the ball.

Static Friction
Weight
Normal Force
Kinetic Friction
Tension
Drag

I'm sure that there is weight and normal force and that there is not tension. I'm also fairly sure that there is no static friction but I am not sure about drag and kinetic friction. I know that this is a pretty easy question but I can not seem to get the hang of it.
 
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I think you need a better understanding of the terms. Static friction is when two solid objects[/color] try to slide[/color] across each other but do not move.

Weight is the Earth pulling down on stuff.

Normal force is when two solid objects[/color] are in contact with each other. It stops objects from going through each other and it's why I can't walk through walls except through a doorway.

Kinetic friction is when two solid objects[/color] slide[/color] across each other. One (or both) of the objects moves.

Tension is when something is being pulled by a rope, a thread, or for that matter any solid object that touches another object but pulls rather than pushes. Tension is between two solid objects[/color] (a rope, for example, is a solid).

Drag is when an object pushes against a liquid or a gas[/color].


So, if the tennis ball, which is a solid, is only touching the air, which is a gas, then is there a normal force between the two?
 
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