Physics

A 1.0-kg ball on the end of a string is whirled at a constant speed of 2.0 m/s in a horizontal circle of radius 1.5 m. What is the work done by the centripetal force during one revolution?

I did:
F=m(v^2)/r
F=1(2^2)/1.5=2.7 J

The answer that was provided was 0. Can someone explain the reasoning? Thanks

  1. 👍
  2. 👎
  3. 👁
  1. It seems to me that centripetal force is directed inward, but the direction of travel is tangent to the circle. How can a force ninety degrees to travel do any work?

    1. 👍
    2. 👎
    👤
    bobpursley
  2. There is no displacement in the direction of the force.
    work=force * displacement in the direction of the force.

    1. 👍
    2. 👎
  3. The object has no displacement during that time, therefore no work is done. Plus the ball traveled at a constant speed which makes the accleration zero, the force zero, and the work zero.

    1. 👍
    2. 👎
  4. Work is transferred, not made.

    1. 👍
    2. 👎
  5. If you look at the final displacement after a full revolution, it will be back where it started. Since work is Force dot Displacement, since displacement is zero, so is work.

    1. 👍
    2. 👎

Respond to this Question

First Name

Your Response

Similar Questions

  1. physics

    A student holds one end of a string in a fixed position. A ball of mass .2 kg attached to the other end of the string moves in a horizontal circle of radius .5m with a constant speed of 5m/s. How much work is done on the ball by

  2. physics

    an object of mass 0.5 kg is whirled at the end of string 0.8 m long if the string make three revolution in 1.2 sec find the tension of the string

  3. physics

    A stone tied to the end of a string, 80 cm long, is whirled in a horizontal circle with a constant speed. If the stone makes 14 revolutions in 25 seconds what is the magnitude and direction of the acceleration of the stone?

  4. physics

    A ball of mass 3.0 kg is tied to the end of a 50-cm length of string. The ball and string are swung in a circle in a vertical plane at constant speed v, which is the minimum speed necessary to keep the string taut at all times.

  1. Physics

    A stone with mass 0.8kg is attached to one end of a string 0.9m long . The string will break if its tension exceeds 600N. The stone is whirled in a horizontal circle ,the other end of the string remains fixed. Find the maximum

  2. physics

    A mass 5kg is whirled in a horizontal circle @ 1 end of a string 50cm long,the other end being fixed. If the string when hanging vertically will just support a load of 200kg mass without breaking,find the maximum whirling speed in

  3. physics

    A ball of mass 200 grams is whirled in a circle at the end of a strong 100 cm long rope whose breaking strength is 10 N. Neglecting gravity, the maximum speed of the ball is approximately.

  4. Physics

    Imagine that you swing about your head a ball attached to the end of a string. The ball moves at a constant speed in a horizontal circle. Part A If the mass of the ball is 0.160kg and you supply a tension force of 14.5N to the

  1. Physics

    A conical pendulum is formed by attaching a ball of mass m to a string of length L, then allowing the ball to move in a horizontal circle of radius r. 1. Find an expression for the tension T in the string. (Express your answer in

  2. Physics

    A stone is tied to a string (length = 0.700 m) and whirled in a circle at the same constant speed in two different ways. First, the circle is horizontal and the string is nearly parallel to the ground. Next, the circle is

  3. Physics

    A ball is tied to one end of a string. The other end of the string is held fixed. The ball is set moving around a vertical circle without friction, and with speed vi = (Rg)1/2. At what angle from the bottom should the string be

  4. Physics

    A ball of mass 0.2 kg tied to string and whirled in a chorizontal circle of radius 0.4 m if ball makes 10 complete revolution in 4secs determine linear speed centripetal acceleration and centripetL force??

You can view more similar questions or ask a new question.