The elastic energy stored in your tendons can contribute up to 35% of your energy needs when running. Sports scientists find that (on average) the knee extensor tendons in sprinters stretch 43 mm while those of nonathletes stretch only 31 mm. The spring constant of the tendon is the same for both groups, 33 N/mm. What is the difference in maximum stored energy between the sprinters and the nonathletes? Express your answer to two significant figures and include the appropriate units. ► View Available Hint(s) 2

A spring of spring constant 20 N/m is stretched as shown. What is the magnitude and direction of the spring force? jo 0.500 m 10 N, to the left zero, no spring force 20 N, to the right 20 N, to the left 10 N, to the right 40 N, to the left 40 N, to the right

0.50 kg - V% = 1.5 m/s r=0.95 m 2.0 m 1.9 m A toy roller coaster is shown above. Ignore friction except where indicated. (c) Calculate the normal force on the cart at point A.

Dust particles fall down when a carpet or a piece of cloth is beaten by a stick, why?