Two air-filled balloons each have a mass of m = 3.1 g. Each balloon hangs from t
ID: 1525041 • Letter: T
Question
Two air-filled balloons each have a mass of m = 3.1 g. Each balloon hangs from the same point by its own string of length L = 0.41 m. Each balloon is rubbed to give it a static charge. Both balloons arc rubbed the same amount, so each balloon has the same unknown charge (q_1= q_2). The hanging balloons push away until each makes and angle of theta =16degree with respect to the vertical. Choose the best Full Body Diagram of the LEFT balloon Write an expression for the magnitude of the repulsive force required to keep the left balloon in this position. |F_E|=_____________________________________________ Determine the magnitude of the charge, in coulombs, on either one of the balloons. Remember that each balloon has the same charge. (q_1 = q_2)Explanation / Answer
B)
In triangle ABC
AC = length of sting = L = 0.41 m
Sin 16 = BC /AC
BC = 0.41 Sin16
r = distance beteween the two balloons = 2BC = 2 (0.41 Sin16) = 0.82 Sin16 = 0.226 m
m = mass of balloon = 0.0031 kg
using equilibrium of forces along the vertical direction
T Cos16 = mg
T Cos16 = (0.0031) (9.8)
T = 0.0316 N
along the X-direction , using equilibrium of forces
F = repulsive force = T Sin16
F = (0.0316) Sin16
F = 0.00871 N
c)
given that : q1 = q2 = q
repulsive force is given as
F = k q1 q2 /r2
0.00871 = (9 x 109) q2 /(0.226)2
q = 2.22 x 10-7 C