EASY PROBLEM - Force to break the string.

AI Thread Summary
To determine the force required to break the string of a toy whistle being whirled in a circle, the mass (0.208 kg) and maximum frequency (3.00 rev/s) are essential. The correct approach involves calculating the centripetal force using the formula F = mv²/r. The velocity can be derived from the maximum revolutions, where one revolution equals 2π radians, leading to a velocity of 6π m/s. Ultimately, substituting the values into the centripetal force equation yields a force of 73.9 N needed to break the string. The calculations highlight the importance of correctly interpreting the problem and applying the relevant physics formulas.
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A .208-kg toy whistle can be whirled in a horizontal circle of 1.00 m radius at a maximum of 3.00 rev/s b4 the string breaks. What is the force needed to break the string.

I don't know how to start this problem but this is what i got.

first i found frequency which is 1/3
and then i got omega = 2pi 1/3

i think this is all wrong because the answer is 73.9N

someone please help!
 
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ook i read the problem wrong so it should be
f=mac
and then f=mv^2/r
so iget 0.208 x v^2 / 1
now how do i get v from the maximum revolution
 
ok i got one revolution is 2pi (obviously)
how do i implement that tothe problem to solve it.
 
If 1 rotation is 2pi, how far does it travel in 1 second? This is the velocity.
 
ok now i got everything I am screwing up with this ti-89
i did 6pi^2 which obviously registered as pi^2 x 6
thanks
 
Last edited:
ok now i got everything I am screwing up with this ti-89
i did 6pi^2 which obviously registered as pi^2 x 6
thanks
 

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