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CornMuffin
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A small 13.0-g bug stands at one end of a thin uniform bar that is initially at rest on a smooth horizontal table. The other end of the bar pivots about a nail driven into the table and can rotate freely, without friction. The bar has mass 70.0 g and is 90 cm in length. The bug jumps off in the horizontal direction, perpendicular to the bar, with a speed of 25.0 cm/s relative to the table.
What is the angular speed of the bar just after the frisky insect leaps?
mass of bug = .013kg
mass of bar = .070kg
length of bar = 0.9m
final velocity of bug = 0.25 m/s
initial velocity of bug = 0
initial velocity of bar = 0
I = (1/3)ML^2
K(bug) = (1/2)mV^2
K(bar) = (1/2)Iw
Sum of the energy before = sum of the energy after
0 = K(bug) + K(bar)
0 = (1/2)mV^2 + (1/2)Iw
0 = (1/2)mV^2 + (1/2)(1/3)ML^2w
w = -[mV^2]/[(1/3)ML^2]
but that doesn't come out with the correct answer
where w is the lowercase omega standing for angular velocity
Homework Statement
What is the angular speed of the bar just after the frisky insect leaps?
mass of bug = .013kg
mass of bar = .070kg
length of bar = 0.9m
final velocity of bug = 0.25 m/s
initial velocity of bug = 0
initial velocity of bar = 0
Homework Equations
I = (1/3)ML^2
K(bug) = (1/2)mV^2
K(bar) = (1/2)Iw
Sum of the energy before = sum of the energy after
The Attempt at a Solution
0 = K(bug) + K(bar)
0 = (1/2)mV^2 + (1/2)Iw
0 = (1/2)mV^2 + (1/2)(1/3)ML^2w
w = -[mV^2]/[(1/3)ML^2]
but that doesn't come out with the correct answer
where w is the lowercase omega standing for angular velocity
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