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**1. Homework Statement**

**1)**A pendulum 1 meter in length is pulled back 12.7 degress and the bob has a mass of 1kg. At the moment the bob is released, a)

**what's the acceleration in m/sec^2 of the bob along the curve of its swing**and b)

**what is the acceleration toward the center of the bob's rotation**?

**2)**For the pendulum in problem 1, how much work was done to pull the pendulum back 12.7 degrees?

**2. Homework Equations**

i think... to get the acceleration of bob along the curve of its swing...you use:

and

and

**a^2+b^2=c^2**

**3. The Attempt at a Solution**

First, i drew the pendulum/free body diagram:

My teacher said to just get a1, which is the acceleration of the bob along the curve of its swing, and a2, the other acceleration.

a)so...

a1=sin(77.3)=opposite/10

.9755=opposite/10

opposite=9.755

9.755^2+b^2=10^2

b^2=4.84

b=2.2

so

**a1=2.2m/sec^2**

b)a2=cos(12.7)=adjacent/10

.9755=adjacent/10

adjacent=9.755

9.755^2+b^2=10^2

b^2=4.84

b=2.2

so

**a2=2.2m/sec^2**

1) i dont think this is right since I get the same accelerations. please help?? Did i do it all right or can you help me solve this problem??

2) All I know is that I need to use the equation

**PE=mgh**and where m is mass, g is gravitational acceleration, and h is the height and

**height=L((1-cos(theta))**. The only thing I really know how to do is get h sine I'm not sure what is L. How do I get that??[/b] HELP ME!!!

THANK YOU!!!

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