Question

A dancer is standing on one leg on a drawbridge that is about to open. The coefficients of static and kinetic friction between the drawbridge and the dancer's foot are μsμsmu_s and μkμkmu_k, respectively. n⃗ n→n_vec represents the normal force exerted on the dancer by the bridge, and F⃗ gF→g represents the gravitational force exerted on the dancer, as shown in the drawing.(Figure 1) For all the questions, we can assume that the bridge is a perfectly flat surface and lacks the curvature characteristic of most bridges.

1. Before the drawbridge starts to open, it is perfectly level with the ground. The dancer is standing still on one leg. What is the horizontal component of the friction force f⃗ f→f_vec? Express your answer in terms of some or all of the variables nnn, μsμsmu_s, and/or μkμkmu_k.

2.The drawbridge then starts to rise. The dancer continues to stand on one leg. The drawbridge stops just at the point where the dancer is on the verge of slipping. What is the magnitude fff of the frictional force now? Express your answer in terms of some or all of the variables nnn, μsμsmu_s, and/or μkμkmu_k. The angle θθtheta should not appear in your answer.

3. Then, because the bridge is old and poorly designed, it falls a little bit and then jerks. This causes the dancer to slide down the bridge. What is the magnitude fff of the frictional force now? Express your answer in terms of some or all of the variables nnn, μsμsmu_s, and/or μkμkmu_k. The angle θθtheta should not appear in your answer.

4. Draw the free-body diagram for a basketball player just before leaving the ground on a jump (see the figure(Figure 1)).Draw the force vectors with their tails at the dot. The orientation of your vectors will be graded. The exact length of your vectors will not be graded but the relative length of one to the other will be graded.

5. Draw the free-body diagram for a basketball player while in the air. Draw the force vectors with their tails at the dot. The orientation of your vectors will be graded. The exact length of your vectors will not be graded but the relative length of one to the other will be graded.

Answer 1

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- (4) free body e body diagram diaq of Basket ball player. Just before jump Nema Mg (5) In The our: No Contact N=0 Q0 ima