Posted by **Casey** on Thursday, January 12, 2012 at 6:47pm.

Could someone verify the answers. I don't know question C and D

Thank you!

1. In physics, the formula for centripetal force is F =

mv^2/

r

where m is the mass, v the velocity, and r the radius.

a) Find the length of a string when a mass of 2.4kg is being spun at a speed of 5 m/sec if the centripetal force

is 15.8 N. Round your answer to the nearest tenth.

Answer: 3.8m

----------------------------------------

b) What length would the string need to be to increase the force to 20.5 N if the speed is 5 m/sec and the

mass is 2.4 kg?

Answer: 2.9m

---------------------------------------

c) If the string is made longer, but the mass and velocity are kept the same, how will this effect the force?

d) What would be the effect on the centripetal force if the mass and velocity were kept the same and the

length of the string was doubled?

- Math -
**Steve**, Friday, January 13, 2012 at 4:21am
a and b are ok

since F varies directly with m and v^2, but inversely with r, increasing r decreases F, as you see if you compare the answers to a and b.

since F varies directly with m and v^2, but inversely with r, doubling r halves F.

## Answer this Question

## Related Questions

physics - there are 3 parts to my question. i need help on the last part. 1.a. A...

math - How much force is needed to accelerate a 50-kg rider and her 250-kg ...

Physics LAST QUESTION - A beetle whose mass is 2 g sits on a turntable at a ...

Check Answers Quick -Physics - What causes the centripetal acceleration of an ...

Physics - I am really confused on the steps to solve this problem. This is my ...

physics - a body of mass 1kg on the equator rotates about the axis of the earth ...

Physics - i have been asking physics questions on this and some people give me ...

physics - I've just read that the centripetal force on an electron is mv^2/r; ...

physics - Consider a 1kg mass at rest at the equator.Because of the earths ...

physics help go! - Two cars are traveling at the same speed of 27 m/s on a curve...