Consider a pendulum bob swinging. The bob follows a circular path which indicates that gravity is not the only force acting upon it.
Identify the additional force; does it affect the equation K + U = 1/2 mv2 + mgh? why or why not?
The Attempt at a Solution
First i cannot figure out if the additional first it is talking about is the force of tension, or the force of friction on the bob by the air.
I want to say its tension but i can't figure out what to say about how tension would affect the equation or not.
If i say it is the friction force due to the air then i can say it doesn't affect the equation for a very long time because it would take the pendulum bob many oscillations before the force of friciton due to the air finally stopped the pendulum.
Any input on this would be very helpful.
Thank you :)