Homework Help: Forces on Pendulum

1. Jun 21, 2014

rputra

I am working on HS Physics teacher certification, the study guide lists one the competencies as follow:

​"Identifies and applies Newton's laws to analyze and solve a variety of practical problems (e.g., properties of frictional forces, acceleration of a particle on an inclined plane, displacement of a mass on a spring, forces on a pendulum)."

Does anyone know the formula for "force on a pendulum"? I know only the period for pendulum. Keep in mind that this is introductory-level physics, any help from experts out there would be very much appreciated. Thanks for your time and effort.

2. Jun 21, 2014

Staff: Mentor

Welcome to the PF.

I did a Google search on Pendulum Physics, and got lots of great hits. Why don't you give that a try, and post any specific questions about that reading here...

3. Jun 21, 2014

HallsofIvy

It's not a matter of a "formula", it's a matter of thinking! There is the force of gravity straight down on the bob of the pendulum of course and there is the force of the pendulum arm toward the pivot that keeps the bob from going straight down. Use a little trigonometry to break that into vertical and horizontal components.