Physics-ch05/ exercise 27
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Question 27





Figure P5.27 shows the horizontal forces acting on a sailboat moving north at constant velocity, seen from a point straight above its mast. At the particular speed of the sailboat, the water exerts a -N drag force on its hull and θ = °. For each of the situations (a) and (b) described below, write two component equations representing Newton’s second law. Then solve the equations for P(the force exerted by the wind on the sail) and for n (the force exerted by the water on the keel). (a) Choose the x direction as east and the y direction as north. (b) Now choose the x direction as θ = 40.0° north of east and the y direction as θ= 40.0° west of north. (c) Compare your solutions to parts (a) and (b). Do the results agree? Is one method significantly easier?

05-27-q-27