physics

posted by .

A tennis ball on a string is being swung in a horizontal circle of radius r. The ball has mass m and the string length l. Which expression gives the magnitude of the tension T in the string in terms only of the speed v of the ball and of m, r, and l?

Answer choices
1. T=mgr/l
2. T=0, as is always the case for a conical pendulum.
3. T=mv^2/l
4. T=mv^2/r
5. T=m[g−(v^2/r)]
6. T=mv^2/2
7. T=mg
8. T=m[g+(v^2/r)]
9. T=mv^2l/r^2

  • physics -

    I do not see where the length of the string (l) comes in the picture if the radius of the circular motion is fixed at r.

    If the ball is swung in air where it is allowed to sag, then there is the horizontal component equal to mv²/r and the vertical component equal to mg.
    The vectorial sum is
    m*sqrt(g²+(v²/r)²)
    which does not correspond to any of the options listed, unless the square-root sign (√) is missing from choices 5 and 8.

  • physics -

    Actual Answer is 9

    SA's answer of 4 is false, I tried it out personally, it doesn't work

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. Physics

    A 3.1 kg ball is tied to a string and swung in a horizontal circle at a speed of 7.2 m/s. the radius of the circle is 2.2 m. What angle does the string make with the horizontal?
  2. 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 terms …
  3. 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. The …
  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 string, …
  5. physics

    A mass M of 2.95 kg is attached to the end of a string whose length is 0.420 m. The mass slides without friction on a horizontal surface as indicated in the diagram. If the string can withstand a maximum tension of 127.5 N, what is …
  6. physics

    a .2 kg ball is being swung around a verticle circle from a 1 m long string, the ball is traveling at 4 m/s counter -clockwise. what is the tension on the string?
  7. Physics

    As shown in the picture to the right, a ball is suspended from the ceiling by a string of negligible mass. When the ball is set into motion such that it moves in a horizontal circle at a constant speed of 1.6m/s, the tension in the …
  8. Physics

    A tennis ball connected to a string is spun around in a vertical, circular path at a uniform speed. The ball has a mass m = 0.162 kg and moves at v = 4.73 m/s. The circular path has a radius of R = 0.87 m 1)What is the magnitude of …
  9. Physics

    A tennis ball connected to a string is spun around in a vertical, circular path at a uniform speed. The ball has a mass m = 0.162 kg and moves at v = 4.73 m/s. The circular path has a radius of R = 0.87 m 1)What is the magnitude of …
  10. Physics

    A 35.0 g ball at the end of a string is swung in a vertical circle with a radius of 35.0 cm. The rotational velocity is 212.0 cm/s. (a)Find the tension (in N) in the string at the top of the circle. (b)Find the tension (in N) in the …

More Similar Questions