Do Weight Differences Affect Speed on a Frictionless Hill?

AI Thread Summary
On a frictionless hill, both a 1-lb block and a 100-lb block will experience the same acceleration due to gravity, regardless of their weight. This means that both blocks will reach the bottom of the hill simultaneously, resulting in a tie. The concept of mass affecting speed is negated by the absence of friction and air resistance. Therefore, the outcome of the race is that both blocks finish together. The conclusion is that weight differences do not affect speed on a frictionless surface.
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Homework Statement



A 1-lb block and a 100-lb block are placed side by side at the top of a frictionless hill. Each is given a very light tap to begin their race to the bottom of the hill. In the absence of air resistance, what can you conclude about the outcome of the race?


Homework Equations





The Attempt at a Solution



This is a multiple choice question. Here are the choices:

1) The 1-lb block wins the race.
2) The 100-lb block wins the race.
3) The two blocks end in a tie.
4) There’s not enough information to determine which block wins the race.


We haven't learned the mathematics behind this question yet. It's a conceptual question. I was thinking, since the hill is frictionless, the 100-lb block should have more force going down the hill than the 1-lb, so I figure that the 100-lb block should win the race. I'm not too confident in my answer though...
 
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In the absence of air resistance and friction, all the objects will have the same acceleration during free fall. It is independent of mass. Sliding down from a hill top is also a free fall.
 
To add to what rl.bhat said, check out this link (http://www.physicsclassroom.com/Class/vectors/u3l3e.cfm). Since you said you haven't learned how to do this yet, it is hard to explain why using equations, so maybe this will help.
 
So the race will be a tie?
 
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Kindly see the attached pdf. My attempt to solve it, is in it. I'm wondering if my solution is right. My idea is this: At any point of time, the ball may be assumed to be at an incline which is at an angle of θ(kindly see both the pics in the pdf file). The value of θ will continuously change and so will the value of friction. I'm not able to figure out, why my solution is wrong, if it is wrong .
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