Find the period of the resulting swings of this pendulum

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SUMMARY

The discussion focuses on calculating the period and amplitude of a pendulum inside a rocket accelerating upward at 3.70 m/s². The user correctly identifies the modified gravitational acceleration as 6.1 m/s² and applies the formula for the period of a pendulum, T = 2π√(L/g), resulting in a period of 2.67 seconds. However, the user struggles with calculating the amplitude, initially misapplying the formula A = x/cos(wt + θ). The correct amplitude calculation requires a clear understanding of the pendulum's displacement and the effective gravitational force.

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Homework Statement


A rocket is accelerating upward at 3.70 m/s^2 from the launchpad on the earth. Inside a small 1.50-Kg ball hangs from the ceiling by a light 1.10m wire.

a)If the ball is displaced 8.50 degrees from the vertical and released, find the amplitude of the resulting swings of this pendulum

b)If the ball is displaced 8.50 degrees from the vertical and released, find the period of the resulting swings of this pendulum

Homework Equations


x=A(coswt+θ)
-mgθ=-mgx/L
θL=x
w=sqrt(g/L)
T=2pi sqrt(g/L)

The Attempt at a Solution


okay first we convert θ into radians whihc is 0.1484 rads
the new g' of the rocket is g-arocket=9.8-3.7=6.1 m/s^2
θL=x 0.1484*1.1=0.16324m
w=sqrt(g/L)=sqrt(6.1/1.1)=2.3549
x=A(coswt+θ)
A=x/cos(wt+θ) now taking t for 0 (this is probably the part where I made my mistake)
A=0.16324/cos(0+0.1484)=0.1148 for the amplitude

b)
T=2pi sqrt(g/L)
T=2pi sqrt(6.1/1.1)=2.67s

In both cases my answers are wrong, if anyone could give me a pointer I would appreciate the help.
 
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the formula for the period is wrong, it should be

T=2*pi*sqrt(L/g)

As for the acceleration, what would it feel like if you were launched in the space shuttle, would you feel lighter or heavier as the rocket was accelerating upwards? In other words how does the acceleration of the rocket combine with the acceleration by gravity?
 


ah that's were I went wrong, Okay I now figured out b but I'm still having difficulty with part a. I'm not sure what to use for my t value.
 

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