physics

Two balls have the same mass of 3.085 kg and identical charges of 21.0 ìC. They hang from the ceiling on strings of identical length as shown in the figure. If the angle with respect to the vertical of the strings is 22.0°, what is the length of the strings

  1. 👍
  2. 👎
  3. 👁
  1. Are the two strings attached to the same point on the ceiling? If so, consider the net torque on either ball about the ceiling attach point. it must be zero.

    The gravity (weight) torque balances the Coulomb-force torque.
    M*g*Lsin22 = k q^2*Lcos22/(2Lsin22)^2

    L can be solved for. Everything else is known

    L^2 = (1/4)[k q^2/(Mg)]*cos22/(sin22)^3

    1. 👍
    2. 👎

Respond to this Question

First Name

Your Response

Similar Questions

  1. Physics

    The force between two identical charges separated by 1 cm is equal to 90 N. What is the magnitude of the two charges?

  2. physics

    Two small pith balls, each of mass m = 11.2 g, are suspended from the ceiling of the physics lab by 1.7 m long fine strings and are not moving. If the angle which each string makes with the vertical is è = 30.4°, and the charges

  3. physics

    Two identical small spheres of mass 2.0g are fastened to the ends of an insulating thread of length 0.60m The spheres are suspended by a hook in the ceiling from the centre of the thread. The spheres are given identical electric

  4. chem11

    Suppose you have a large supply of sponge balls with weights in the centre, so that when the balls are piled on each other the bottom ones are flattened. Sketch a graph that generally describes mass vs. volume for these sponge

  1. Physics

    Pith Balls Two small pith balls, each of mass m = 17.7 g, are suspended from the ceiling of the physics lab by 0.8 m long fine strings and are not moving. If the angle which each string makes with the vertical is è = 42.6°, and

  2. Physics

    two identical brass balls mounted on wooden posts initially have different amounts of charge, one plus 3 uC and the other plus 15 uC. The balls are allowed to touch and then separate again. What is the final charge on each ball?

  3. physics

    A 500-kg cannon and a supply of 80 cannon balls, each with a mass of 45.0 kg, are inside a sealed railroad car with a mass of 11000 kg and a length of 49 m. The cannon fires to the right; the car recoils to the left. The cannon

  4. AP Physics

    Two identical, small balls are suspended by separate 0.25m threads that are attached to a common point on the ceiling. Each ball has a mass of 8.0 x 10^-4 kg. Initially the balls are uncharged and hang straight down. They are then

  1. physics

    Two balls are approaching each other head-on. Their velocities are +11.9 and -10.5 m/s. Determine the velocity of the center of mass of the two balls if (a) they have the same mass and (b) if the mass of one ball (v = 11.9 m/s) is

  2. Trig/Pre-Calc

    $2500 is invested in an account at interest rate r, compounded continuously. Find the time required for the amount to (a) double and (b) triple. r=0.085 I know you use the formula A=Pe^rt and you would start by setting it up as

  3. physics

    Two identical steel balls, each of mass 5.0 kg, are suspended from strings of length 29 cm so that they touch when in their equilibrium position. We pull one of the balls back until its string makes an angle θ = 25° with the

  4. physics

    Calculate the density of the balls in this area. Each ball has a mass of 1 kg. Estimate the area taken up by the whole structure by looking in the Parameters Palette for the diameter of the balls and multiplying this by the number

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