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CollegeStudent
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Homework Statement
A mass of 200 g is attached to the end of a cord 1.20 m long. The cord is hung from a horizontal beam and the mass is free to swing making a pendulum. The mass is released from rest at an angle of 60° from vertical. What will be the velocity of the mass at an angle of 30°, and at an angle of 0°?
Homework Equations
F_c = m(v²/r)
The Attempt at a Solution
I figured that since it seems to be traveling in a half circle type of movement...I could use the fact that the length of the string would be the radius...so 1.20m
after that I did
ƩF_y = ma_y
mgcosθ = m(v²/r)
the m's cancel so
gcosθ = v²/r
v = √(rgcosθ)
And I figured that I could use that same equation to solve for each of the angles...i.e
= √((1.20(9.8cos60))
= √((1.20(9.8cos30))
= √((1.20(9.8cos0))
Would this be correct? Or am I totally off here?