A 280 g block on a 52.0 cm-long string swings in a circle on a horizontal, frictionless table at 85.0 rpm.
What is the speed of the block?
What is the tension of the string?
2007-10-28 09:18:12 · 1 answers · asked by Anonymous in Science & Mathematics ➔ Physics
The block is going in a circle with radius 52 cm. It does 85 revolutions in a minute. So it has gone the distance of one circumference X 85 in a minute. That gives you the speed.
Keeping the block moving in a circle requires centripetal force towards the center.
Fc = m*v^2 / r
That force is provided by the tension.
Edit: Force is measured in Newtons. Your units are not in the right combination to yield Newtons. You'll have to convert the g to kg and the cm to meters and the minutes to seconds. Then you need to know that
1 Newton = 1 kg*m*/s^2
2007-10-28 10:49:13 · answer #1 · answered by sojsail 7 · 0⤊ 0⤋