- #1
Schulze
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Homework Statement
A particle rotates counterclockwise in a circle
of radius 4.4 m with a constant angular speed
of 11 rad/s. At t = 0, the particle has an x
coordinate of 2.9 m and y > 0 .
Part 1: Determine the x coordinate of the particle velocity
at t = 1.22 s.
Answer in units of m/s
Part 2: Determine the x coordinate of the particle acceleration
at t = 1.22 s.
Answer in units of m/s2
Homework Equations
x = Acos(wt + d)
where d was found in a previous part of the problem and confirmed correct by the program to be:
d = 0.8511870029
v = -wAsin(wt + d); vx = -wRsin(wt) = -vsin(wt)
a = -w2Acos(wt + d)
Note R and A are interchangeable
The Attempt at a Solution
Part 1:
Attempt 1: v = -wAsin(wt + d) = -(4.4 m)sin(11rad/s * 1.22s + 0.8511870029)
v = -4.360544081 m/s
Incorrect
Attempt 2: vx = -wRsin(wt)
vx = -(11rad/s)(4.4m)sin(11 rad/s * 1.22 s) ≈ -36.477666 m/s
vx = -vsin(wt) = (solution from Attempt 1)sin(wt)
vx = -(-4.360544081 m/s)sin(11 rad/s * 1.22 s) ≈ -3.286414681 m/s
Vastly different answers, don't know if incorrect because I don't want to get points deducted from score from trying random answers