A pendulum swings through an angle of 20 degrees each second. If the pendulum is 40 inches long, how far does its tip move each second?

Answer 1

to answer this question you need to know the formula for the circumference of a circle is: circumference = pi * 2r and a circle is 360 degrees.

so the length of the arc is what fraction of the whole circle?

and that fraction times the above circumference formula is your answer