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A 76 kg boater, initially at rest in a stationary 45 kg boat,
steps out of the boat and onto the dock. If the boater moves out
of the boat with a velocity of 2.5 mls to the right, what is the
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Each croquet ball in a set has a mass of 0.50 kg. The green ball,
traveling at 12.0 mis, strikes the blue ball, which is at rest.
Assuming that the balls slide on a frictionless surface and all
collisions are head-on, find the final speed of the blue ball if:
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A boy on a 2.0 kg skateboard initially at rest tosses an 8.0 kg
jug of water in the forward direction. If the jug has a speed of
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mls relative to the ground and the boy and skateboard move in
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the opposite direction at 0.60 mis, find the boy's mass.
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A 1,850 kg luxury sedan stopped at a traffic light is struck from
the rear by a compact car with a mass of 975 kg. The two cars
become entangled as a result of the collision. If the compact car
was moving at a velocity of 22.0 mls to the north before the
collision, what is the velocity of the entangled mass aft~r the
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A grocery shopper tosses a 9.0 kg bag of rice into a stationary
18.0 kg grocery cart. The bag hits the cart with a horizontal
speed of 5.5 m/s toward the front of the cart. What is the final
speed of the cart and bag? i\o\elc;s+(£ (+~e~ v....o"e t03ef"'t'\" after)
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A 47.4 kg student runs down the sidewalk and jumps with a
* horizontal speed of 4.30 m/s onto a stationary skateboard.
(Y.~~ ~ e~ Jstudent and skateboard move down the sidewalk with a speed
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a) Find the mass of the skateboard
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b) Find how fast the student would have to jump to have a final
speed of 5.00 m/s
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Two 0.40 kg soccer balls collide elastically in a head-on
collision. The first ball starts at restJ and the second ball has
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rest. What is the final speed of the first ball?
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A tennis player places a 55 kg ball machine on a frictionless
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with a velocity of 36 m/s toward the north. What is the final
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velocity of the machine?
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A 25.0 g marble sliding to the right at 20.0 cm/s overtakes an
collides elastically with a 10.0 g marble moving in the same
direction at 15.0 cm/s. After the collision, the 10.0 g marble
moves to the right at 22.1 cm/s. Find the velocity of the 25.0 g
marble after the collision.
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A 73e N student stands in the middle of a frozen pond having a
radius of s.e m. He is unable to get to the other side because of
a lack of friction between his shoes and the ice. To overcome
this difficultYJ he throws his 2.6 kg physics textbook
horizontally toward the north shore at a speed of s.e m/s. How
long does it take him to reach the south shore?
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A lJSSe kg car moving south at le.e m/s collides with a 2JSSe kg
car moving north. The cars stick together and move as a unit
after the collision at a velocity of S.22 m/s to the north. Find
the velocity of the 2JSSe kg car before the collision. M.::: Z.SS"o,~
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A e.e2S kg golf ball moving at 18.e m/s crashes through the
window of a house in 5.ex1e-4 s. After the crashJ the ball
continues in the same direction with a speed of le.e m/s.
Assuming the force exerted on the ball by the window was
constantJ what was the magnitude of this force?
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