Now, letâs get down to business â the cost! They do offer a 30 day free trial and then after that it is $7.95 a month or $79 a year. After just a few weeks of Nathan playing, I personally feel that the $7.95 a month is totally worth it!
A pendulum is a weight suspended from a pivot so that it can swing freely. When a pendulum is displaced sideways from its resting, equilibrium position, it is subject to a restoring force due to gravity that will accelerate it back toward the equilibrium position.
Here, l is the length of the pendulum and g is a measure of gravity's strength (what we call the acceleration due to gravity). You can see from this equation that you need to quadruple the length of a pendulum to double the time it takes to make a swing.