SOLUTION: Please help me solve this word problem... A pendulum in a grandfather clock is 4 feet long and swings back and forth along a 6-inch arc. Approximate the angle in degrees through

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Question 402881: Please help me solve this word problem...
A pendulum in a grandfather clock is 4 feet long and swings back and forth along a 6-inch arc. Approximate the angle in degrees through which the pendulum passes during one swing.
Thank You!!!
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
The formula for the length of the arc 's' given a radius 'r' and and angle 'x' is s=rx Note: x is in radians


In your case, s=6%2F12=1%2F2 (I'm converting to feet) since it moves along a path that's half a foot long. So s=1%2F2


Also, we're given that the pendulum is 4 ft long. So r=4


Plug all of this into the formula above to get 1%2F2=4x and solve for x to get x=1%2F8


So the angle is 1%2F8 of a radian. Now convert this to degrees to get %281%2F8%29%28180%2Fpi%29=7.1619724391353 (which is approximate)


So the angle in degrees is about 7.16 degrees