• Support PF! Buy your school textbooks, materials and every day products via PF Here!

Simple Pendulum

  • Thread starter vroman
  • Start date
A simple pendulum consists of a mas M suspended by a thin string. The magnitude of the tension is T. The mass swings back and forth between +,- theta0.
I need help identifying which of the following statements are correct. These are my answers, but I'm getting something wrong.

A)T=Mg at some angle between zero and theta0 not correct
B)T is largest at the bottom (theta=0)
C)The vertical component of tension is constant Correct
D)T is smallest when theta=+,- theta0
E)T depends on theta Correct
F)T equals Mg when theta=theta0
Not correct
G)T is greater than Mg for theta =theta0 Not correct

I would really appreciate some help with this problem, Thanks!!


Science Advisor
Homework Helper
Insights Author
Discuss "A".Why do you think it is incorrect...?

Because I thought T=mg at 0.


Science Advisor
Homework Helper
vroman said:
Because I thought T=mg at 0.
Only if the mass is not accelerating at 0, and the only time that happens is if the mass is at rest at zero. Your mass is always moving at 0. What is the direction of acceleration at that point?

Physics Forums Values

We Value Quality
• Topics based on mainstream science
• Proper English grammar and spelling
We Value Civility
• Positive and compassionate attitudes
• Patience while debating
We Value Productivity
• Disciplined to remain on-topic
• Recognition of own weaknesses
• Solo and co-op problem solving