Skateboarder with a mass of 150kg

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A skateboarder with a mass of 150 kg collides with a stationary steel dumpster, coming to a stop in 0.25 seconds from an initial velocity of 13 m/s. The rate of acceleration during the stop is calculated as -52 m/s². The force exerted on the dumpster is determined to be 7800 N, based on the change in momentum. The calculations confirm the relationships between time, acceleration, and change in velocity. The discussion emphasizes the application of physics equations to analyze the collision scenario.
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A skateboarder with a mass of 150 kg is traveling at a final velocity of 13m/s and collides with a steel dumpster. The dumpster does not move. The skateboarder comes to a stop at 0.25 seconds. What is his rate of acceleration as he stops? How much force does he exert on the dumpster?

Can someone help me please.
 
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Can you write down an equation for the relationship between time, acceleration and change in velocity?
 
Initial velocity= 13ms^-1
Final velocity= 0ms^-1
Time= 0.25s

A) Rate of acceleration = (V-U)/T = (0-13)/0.25 = -52ms^-2

B) Force exerted on the dumpster= F= (MV)/ T = (150*13)/0.25 = 7800N

I think?
 
That looks correct to me! Average acceleration is change in velocity divided by change in time. Force exerted is equal to the change in momentum.
 
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