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WadeS
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Conservative Forces and Potential Energy
A mass hangs on the end of a massless rope. The pendulum is held horizontal and released from rest. When the mass reaches the bottom of its path it is moving at a speed v = 2.1 m/s and the tension in the rope is T = 19.3 N.
1)
How long is the rope?
So we know that the velocity at the bottom is 2.1m/s, and the T is 19.3, we are looking for the length of the rope, L
I was using v=square root of (gl)
then tried using : v^2= 2gL
none of which gave my the correct answer
2.1^2=2(9.81)L
L=2.1^2/2(9.81)= .22 m
if anyone can provide a clarification for this, it is a simple problem which I should be able to figure out but whether I am using the wrong equation or simply plugging it in wrong , I am unsure. Any help and guidance is much appreciated!
Regards,
Homework Statement
A mass hangs on the end of a massless rope. The pendulum is held horizontal and released from rest. When the mass reaches the bottom of its path it is moving at a speed v = 2.1 m/s and the tension in the rope is T = 19.3 N.
1)
How long is the rope?
So we know that the velocity at the bottom is 2.1m/s, and the T is 19.3, we are looking for the length of the rope, L
Homework Equations
I was using v=square root of (gl)
then tried using : v^2= 2gL
none of which gave my the correct answer
The Attempt at a Solution
2.1^2=2(9.81)L
L=2.1^2/2(9.81)= .22 m
if anyone can provide a clarification for this, it is a simple problem which I should be able to figure out but whether I am using the wrong equation or simply plugging it in wrong , I am unsure. Any help and guidance is much appreciated!
Regards,
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