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In Figure (a), a 4.8 kg dog stands on a 16 kg flatboat at a distance D = 9.2 m from the shore. He walks 1.9 m along the boat toward shore and then stops. Assuming no friction between the boat and the water, find how far the dog is then from the shore. (Hint: See Figure (b). The dog moves leftward and the boat moves rightward, but does the center of mass of the boat + dog system move?) (a) Dog's displacement da Boat's displacement do (b) Number UnitsA 0.26 kg softball has a velocity of 17 m/s at an angle of 49 below the horizontal just before making contact with the bat. What is the magnitude of the change in momentum of the ball while it is in contact with the bat if the ball leaves the bat with a velocity of (3)16 m/s, vertically downward, and (b)16 m/s, horizontally back toward the pitcher? (a) Number a Units V (b) Number n Units V A force in the negative direction of an x axis is applied for 30 ms to a 0.52 kg ball initially moving at 20 m/s in the positive direction of the axis. The force varies in magnitude, and the impulse has magnitude 30.1 N s. (a) What is the ball's velocity (including sign for direction) just after the force is applied? (b) What is the average magnitude of the force on the ball? (a) Number n Units v (b) Number n Units V _.. _..-. .---...,.-... . . _a. v..- It is well known that bullets and other missiles red at Superman simply bounce off his chest. Suppose that a gangster sprays Superman's chest with 4.9 g bullets at the rate of 130 bullets/min, and the speed of each bullet is 550 m/s. Suppose too that the bullets rebound straight back with no change in speed. What is the magnitude of the average force on Superman's chest from the stream of bullets? Number a Units v A soccer player kicks a soccer ball of mass 0.45 kg that is initially at rest. The player's foot is in contact with the ball for 1.90 x 10'3 s, and theforce of the kick is given by Flt) = [(7.34 x 105)t- (3.86 x 103)t2] N forO g t g 1.90 x 10-3 s ,where t is in seconds. Find the magnitudes of the following: (a) the impulse on the ball due to the kick, (b) the average force on the ball from the player's foot during the period of contact, (c) the maximum force on the ball from the player's foot during the period of contact, and (cl) the ball's speed immediately after it loses contact with the player's foot. (3) Number I Units v (b) Number n Units V (c) Number a Units V (cl) Number Units v