a pendulum swings back and forth taking 2 seconds to move from the position directly above from point a to the position directly above point b, as shown in the figure below. the distance form a to b is 20 cm. let d be the horizontal distance from her pendulum to the (dashed) centre line at time t seconds (with distances to the right of the line measured by positive numbers and distances to the left by negative ones). assume that the pendulum is on the centre line at time t = 0 and moving to the right.

Question

a) assume that the motion of the pendulum can be described by a sinusoidal function. Sketch the graph of d versus t for 0<\ t <\ 8.

b) write a sine equation that describes your graph

Answer 1

I can't see the figure, but if A and B are both 10 cm from the center line, then the maximum value of d is 10. This is the amplitude of the sine function desired, so since the period is 2 seconds,

d = 10sin(πt)

Answer 2

a) assume that the motion of the pendulum can be described by a sinusoidal function. Sketch the graph of d versus t for 0<\ t <\ 8.

b) write a sine equation that describes your graph

Answer 3

what don't you like about what I wrote?

Answer 4

How would I draw this

Answer 5

geez - you know how to draw a sine curve, right?

So, draw your generic sine curve, but instead of -1 to 1 on d, label it -10 to 10

and on the t axis, instead of a period going from 0 to 2π, label the axis so it goes from 0 to 2.

Sine curves all look the same. Just label the axes as you need for the amplitude and period.