r = 0.56/2 = 0.28 meters
period = .75 s
so the block goes 2 pi r meters in 0.75 seconds
v = 2 pi *.28 / 0.75 = 2.35 meters/second
F = mass * centripetal acceleration
= m v^2/r
= 1.5 * 2.35^2/.28 = 29.5 Newtons
A light string of length of 56.0 cm connects two small square blocks, each with a mass of 1.50 kg. The system is placed on a
slippery (frictionless) sheet of horizontal ice and spun so the two blocks rotate uniformly about their common
center of mass,
which itself does not move. They are supposed to rotate with a period of 0.750 s. If the string can exert a force of only 100
N
before it breaks, determine whether this string will work.
All i know is the answer is 29.5N but i dont know how they got that answer. help????
3 answers
Thank you!
You are welcome.