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SherlockOhms
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Homework Statement
A pendulum of mass "m" reaches a height "h" , while the length of the pendulum is R. If the R = 262 cm and h = 136 cm: (a) calculate the max speed in the x-direction.
(b) calculate the max speed in the y direction.
Homework Equations
K = 1/2(m)(v)^2.
U = mgh.
Vector components.
The Attempt at a Solution
Calculating the max speed in the x direction is grand, it obtains a maximum value at the bottom of the arc so using conservation of energy you can calculate it to be v = sqrt(2gh). This is due to the vector components of the pendulum's velocity being v = vcos(θ)x + vsin(θ)y. The x-component obtains a max value when cos(θ) = 1 which occurs at θ = 0 (i.e. the bottom of the arc). Wouldn't the y-component then obtain a max value when θ = pi/2? This angle is never actually reached due to the bob only being raised through a height "h".
So calculating the max velocity in the y is a little trickier. Could somebody give me some advice on what to do next? I'll attach a picture of the diagram.