2 Balls on inclined plane problem

AI Thread Summary
Identical balls rolled down two inclined planes of the same height but different angles will not reach the bottom at the same time due to their differing lengths and inclines. The steeper incline allows the ball to accelerate faster, while the shallower incline results in a longer distance to travel. When neglecting friction and air resistance, the balls slide rather than roll, affecting their speeds. The discussion emphasizes the importance of considering both forces and energy in analyzing the problem. Ultimately, the balls will have different speeds upon reaching the bottom due to the variations in incline and distance.
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Identical balls are rolled down 2 inclined planes of the same height but different inclines. Do they reach the bottom at the same time. Neglect friction and air resistance.

Do the balls have the same speed upon reaching the bottom of the incline? :rolleyes:
 
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do u mean planes of the same length?
 
In my homework assignment, it doesn't mention length. Alicia0
 
Bama said:
In my homework assignment, it doesn't mention length. Alicia0
The inclines cannot have the same length. The balls start from the same height, but one rolls down a shorter plane at a steeper angle.

The first question requires that you think in terms of forces and acclerations. The second is best thought about in terms of energy.
 
Bama said:
Identical balls are rolled down 2 inclined planes of the same height but different inclines. Do they reach the bottom at the same time. Neglect friction and air resistance.

Do the balls have the same speed upon reaching the bottom of the incline? :rolleyes:

If the friction is neglected the balls will slide, will not roll at all.
 
Imagine one incline almost vertical. How long would it take the ball to reach the ground?

Imagine the other incline with a tiny angle from the horizontal so its length is one mile. How long do you think it will take the ball to cover that one mile?
 
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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