Kendra F. answered • 02/27/17

Patient & Knowledgeable Math & Science Tutor

The pendulum starts being timed at equilibrium position, this suggests you use a sine function since sin(0)=0

The time it takes to make one full revolution is what's called the period, represented by a T. You are given T= 4 sec. The distance from equilibrium is the amplitude, A of the function which is given to be 6 in.

General wave function:

f(t) = A*sin( t*2pi/T - b) + c

A = |amplitude| ; distance from the midpoint

T = period ; time it takes to make one full revolution

b = shifts the graph right/left

c = shifts the graph up/down

This graph lies right on the axis so there will be no need to shift the graph

f(t) = 6*sin(t*pi/2)

y-axis will be units of inches and x-axis, seconds