A 10 kg mass is tied to a 5 kg cart as shown on the left. The 10kg mass is dropped and accelerates at a rate of 9.8m/s/s pulling the cart along the table. What is the force acting on the cart? Assume no friction.   The total mass that accelerates at 9.8m/s/s is 15kg( 10kg mass + 5kg cart). So the expression below F= m X a F = 15 X 9.8 = 147 N

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A 20 kg mass is tied to a 5 kg cart as shown on the left. The 20kg mass is dropped and accelerates at a rate of 9.8m/s/s pulling the cart along the table. What is the force acting on the cart? Assume no friction. The total mass that accelerates at 9.8m/s/s is 25kg( 20kg mass + 5kg cart). So the expression below F= m X a F = 25 X 9.8 = 245 N

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A red billiard ball of mass 250g accelerates at 15m/s/s and collides into a blue, ball of mass 300g. The red ball comes to a sudden stop while the blue ball accelerates in a straight line. What is the acceleration of the blue ball?

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Assuming no friction the force that the red ball collides with is the force that accelerates the blue ball along the table. SO!

m(blue ball) X a = m(red ball)X a
0.25kg X 15m/s/s = 300 X a
a = 0.0125m/s/s

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