Tension in a conical pendulum's string

AI Thread Summary
The discussion focuses on solving the tension in the string of a conical pendulum and determining the period of its motion. The parameters include a bob mass of 0.050 kg, a string length of 0.90 m, and a circular path circumference of 0.94 m. Key equations involve calculating the radius of the circle, the angle of the string with the vertical, and the relationships between tension, gravitational force, and centripetal force. The user initially struggled with finding the velocity but ultimately resolved the problem by referencing another forum thread. The successful resolution of the problem led to a sense of joy and accomplishment.
mbrmbrg
Messages
485
Reaction score
2
The problem:
Figure 6-43 shows a "conical pendulum", in which the bob (the small object at the lower end of the cord) moves in a horizontal circle at constant speed. (The cord sweeps out a cone as the bob rotates.) The bob has a mass of 0.050 kg, the string has length L = 0.90 m and negligible mass, and the bob follows a circular path of circumference 0.94 m.
(a) What is the tension in the string?
(b) What is the period of the motion?

I found:
radius of the circle=circumference/2pi
angle that string makes with vertical=arcsin(r/l)
T_y=mg
T_x=F_centripetal=ma=mv^2/r

I would like very much to find v, but I don't see how using omega will be at all helpful. period=(2)(pi)(r)/v doesn't seem to get me anywhere, either.
 
Physics news on Phys.org
Whoa, never mind! I searched the forum and found "Conical Pendulum Problem -Right Way of Solving?" and solved the problem correctly. Joy and Jubilation!
 
Kindly see the attached pdf. My attempt to solve it, is in it. I'm wondering if my solution is right. My idea is this: At any point of time, the ball may be assumed to be at an incline which is at an angle of θ(kindly see both the pics in the pdf file). The value of θ will continuously change and so will the value of friction. I'm not able to figure out, why my solution is wrong, if it is wrong .
TL;DR Summary: I came across this question from a Sri Lankan A-level textbook. Question - An ice cube with a length of 10 cm is immersed in water at 0 °C. An observer observes the ice cube from the water, and it seems to be 7.75 cm long. If the refractive index of water is 4/3, find the height of the ice cube immersed in the water. I could not understand how the apparent height of the ice cube in the water depends on the height of the ice cube immersed in the water. Does anyone have an...

Similar threads

Back
Top