Physics

A ball (m = 250g) on the end of
string swings in 1.2 m radius that tolerates 20 N. At what speed does the string breaks if
a) the rings swings horizontally ?
b) the rings swing vertically?

I think I got a) right:
T=mv2/r ---> v=(sqr)Tr/m

v=(sqr) 20x1.2/0.25= 9.8 m/s

Given answers are: 9.8 m/s and 9.2 m/s

Can someone help me how to find maximum speed when the rings swings vertically please ? :)

asked by Physics: Circular Motion?
  1. Max force at bottom = 20 = m v^2/r + m g

    20/.25 = v^2/1.2 + 9.81

    v^2 = 70.19 *1.2 = 84.2

    v = 9.17 m/s

    posted by Damon

Respond to this Question

First Name

Your Response

Similar Questions

  1. Physics

    A 300 ball swings in a vertical circle at the end of a 1.2-m-long string. When the ball is at the bottom of the circle, the tension in the string is 13 . What is the speed of the ball at that point?
  2. physics

    A 500 {\rm g} ball swings in a vertical circle at the end of a 1.5-m-long string. When the ball is at the bottom of the circle, the tension in the string is 14 {\rm N}.What is the speed of the ball at that point?
  3. physics

    A 3.6 -kg mass attached to the end of a string swings in a vertical circle (radius = 17.9 m). When the string is horizontal, the speed of the mass is 3.8 m/s. What is the magnitude of the force of the string on the mass at this
  4. Science

    A uniform metal ball (mass m) is tied to the end of a string (massless, length L). The other end of the string is fixed. The ball is moving in a vertical circle centered at the fixed end of the string. Suppose the velocity of the
  5. 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
  6. PHYSICS!!

    A ball on the end of a string is whirled around in a horizontal circle of radius 0.386 m. The plane of the circle is 1.10 m above the ground. The string breaks and the ball lands 2.00 m (horizontally) away from the point on the
  7. Physics

    A ball on the end of a string is whirled around in a horizontal circle of radius 0.300m. The plane of the circle is 1.19m above the ground. The string breaks and the ball lands 1.91m (horizontally) away from the point on the
  8. Physics

    A ball whirls around in a vertical circle at the end of a string. The other end of the string is fixed at the center of the circle. Assume that the total energy of the ball-Earth system remains constant. (a) What is the tension in
  9. physics

    A ball whirls around in a vertical circle at the end of a string. The other end of the string is fixed at the center of the circle. Assume that the total energy of the ball-Earth system remains constant. (a) What is the tension in
  10. physics

    I need help coming up a source of error for this like lab thing that we are doing class. So like we took this string with a rubber ball on it and the string went through a glass tube, and on the end of the string, so the like

More Similar Questions