SOLUTION: Suppose the pendulum string is attached to a point on the ceiling 30 cm from the wall. The weight is moved away from its rest position and released at time t=0. At time t=1.4 sec,

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Question 1079694: Suppose the pendulum string is attached to a point on the ceiling 30 cm from the wall. The weight is moved away from its rest position and released at time t=0. At time t=1.4 sec, it reaches its maximum distance from the wall, 37.4 cm away, and then swings back toward the wall again. At times 2.8 sec, the weight reaches a minimum distance of 23.2 cm form the wall, and then swings away again.
a. assuming that the amplitude of the pendulum's swing decreases exponentially with the time, find an equation expressing the amplitude A in terms of time t.
b. find an equation modeling the weight's distance from the wall
c. at the moment the weight was released, what angle did the string make with the ceiling
Can someone help me with this?
Thanks
Answer by KMST(5328) About Me  (Show Source):
You can put this solution on YOUR website!
HINTS:
In physics, the period of a pendulum is supposed to be a constant,
depending on the length of the string, L ,
and the acceleration of gravity, g=about9.8m%2Fs%5E2 :
T=2pi%2Asqrt%28L%2Fg%29 .
The period is the time between two consecutive times the pendulum is closest to the wall.

If you know the pendulum started at A%5B0%5D away from the vertically down equilibrium position,
swinging in an arc of radius L ,
you can calculate the initial angle between string and the vertical.

Assuming the ceiling is horizontal, you can relate that to
the initial angle between the string and the ceiling.