A 1.3 Kg ball is moving on a horizontal frictionless surface with 10m/s. It collides with a vertical wall and rebounds back with forth of its kinetic energy before the collision. What is the magnitude of the force on the ball from the wall if the contact time is 12.6 ms?

A2 kg ball travellng to the right with a speed of 4 m/s collidees with a 5 kg ball traveling to the left with a speed of 3 m/s. take right to be the positive direction. what is the total momentum of the two balls before they collide? what is the total momentum of the two balls after they collide?

Blank liquids and gases exert a buoyant force on objects placed in them

30 points - when can a theory be modified if a new type of technology allows for new observations that raise new questions? a. immediately, while the questions about the theory are being asked b. after new hypotheses related to the theory are tested in experiments c. only after the new observations disprove all parts of the theory d. while scientists begin to think about how the theory could improve