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During an Olympic 100-m sprint race, Usain Bolt, the world record holder in that race, quickly accelerates to his top speed of 12.4 m/s. Analysis of his technique has shown that each of his feet make contact with the ground for 0.0800 s, exerting a force of magnitude 2.80 x 10° N during this contact. This allows the 94.0 kg Bolt to leap forward and remain airborne for 0.120 s until the next foot touches the ground. (Ignore air resistance.) (a) What are the magnitudes of the horizontal and vertical components of the force (in N) Bolt's feet exert on the ground? (Round your answers to at least three significant figures.) horizontal N vertical (b) Assuming that the sprinter accelerates at a constant rate while his feet are in contact with the ground and does not slow down when he is airborne, by what amount does Bolt's horizontal speed (in m/s) increase with each step? (Round your answer to at least three significant figures.) m/s (c) Assuming that the sprinter's speed increases at a…

A 42-lb suitcase slides from the rest 20 ft down the ramp. The suitcase has an initial velocity down the ramp of v_A = 7 ft/sft/s and the coefficient of kinetic friction along AB is μk = 0.19. (Figure 1) (a)  How long does it take to go from A to C? Express your answer to three significant figures and include the appropriate units. The answer is not 1.561 seconds.

Two spheres of different masses and initial velocities collide with each other on frictionless surface, as shown in Figure 5. Assume the collision is direct central and the coefficient of restitution e = 0.8, determine their velocities after the collision.