Circular Motion Old Spec question
Physics and electronics discussion, revision, exam and homework help.
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Circular Motion Old Spec questionThis is from an old spec paper and the question has come up twice; Jan03 and June09
In jan03 the answer is D but in june09 the answer is B
Not sure which answer is right and have no idea how to do this :/
Help please!Last edited by X1tinkerbellx; 10-06-2012 at 14:49. -
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Re: Circular Motion Old Spec questionI'd think it was B.
v/r = pi/2
v = 2/5 pi
circumference = 1.6pi
1.6/0.4 = 4
6/4 = 1.5
So it does 1.5 rotations from P in 6 seconds so it ends up exactly opposite P in the circle which is just the diameter 1.6m
Edit: In fact, I just remembered the way I did it first time I saw this question lol, much simpler.
Just count pi/2 6 times from P.
So count 6 quarters from P because pi/2 is a quarter of a circle.Last edited by justravi; 10-06-2012 at 15:23. -
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Re: Circular Motion Old Spec questionThanks!(Original post by justravi)
I'd think it was B.
v/r = pi/2
v = 2/5 pi
circumference = 1.6pi
1.6/0.4 = 4
6/4 = 1.5
So it does 1.5 rotations from P in 6 seconds so it ends up exactly opposite P in the circle which is just the diameter 1.6m
Edit: In fact, I just remembered the way I did it first time I saw this question lol, much simpler.
Just count pi/2 6 times from P.
So count 6 quarters from P because pi/2 is a quarter of a circle.
