Physics Questions: Frictionless Surfaces, Astronauts, Tennis Balls

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On a frictionless surface, a person cannot walk as there is no friction to provide the necessary grip; they can only move by pushing off against another object. In the scenario with astronauts, when one throws the other, they will both move in opposite directions due to conservation of momentum, and the game will continue until they drift too far apart to throw again. The tennis ball's collision with the wall demonstrates that while it bounces back with the same speed, momentum is not conserved in this case because the wall absorbs some momentum. The discussion emphasizes the principles of physics governing motion and interactions in different environments. Understanding these concepts is crucial for analyzing real-world applications and scenarios in physics.
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1. A person is standing on a completely frictionless surface. Can they walk on this surface? Explain! What could they do to move across the surface? Explain!

2. Suppose there are three astronauts outside their spaceship and that two of them decide to play catch with the third. This means the first two astronauts are attempting to throw the third back and forth. All astronauts weigh the same on Earth and are equally strong. The first throws the second and the game begins. Describe the motion of the astronauts as the game proceeds. How long will the game last (i.e. how many throws) ?

3. When a tennis ball is thrown against a wall it appears to bounce back with exactly the same speed as it struck the wall. is momentum conserved for this collision? explain
 
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