Recent content by demenius

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    Mass in circular motion. Draw Diagram and find/explain variables.

    Ok. So Fx = Fsinθ = ma_rad Fy = Fcosθ - mg = 0 (no vertical acceleration) a_rad = (4R∏^2)/T^2 R = Lsinθ F = mg/cosθ Sub into Fx (mg/cosθ)*sinθ = ma_rad a_rad = gtanθ gtanθ = (4R∏^2)/T^2 T = √((4R∏^2)/gtanθ) = 2∏√(R/(gtanθ)) Sub in Lsinθ for R T = 2∏√(Lcosθ/g)
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    Mass in circular motion with friction. Find max height.

    The Speed at the bottom would be √(2gR) = 12.53. Assuming the frictional part was flat the velocity after the the frictional part would be 12.12. And the max height would be 7.499m. But if the frictional part was not flat and was part of the semi circle then I am lost on how to do it.
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    Bullet passing through block of wood. Find max height of the wood.

    So would the height be equal to (v*mb/(mb+mw))^2 * 1/2g? So. (200*0.005/(0.005+1))^2 *1/2(9.81) = 0.05m?
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    Mass in circular motion. Draw Diagram and find/explain variables.

    http://imageshack.us/photo/my-images/412/freebodydiagram.png/" I found T to be equal to 2∏√(Lcos(θ)/g). But there is no m in that equation. Is it not needed? If that equation is right, then when θ increases, T would decrease.
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    Mass in circular motion with friction. Find max height.

    I know how to calculate the speed at the bottom but the friction part is before the bottom and I cannot figure out how to calculate the speed just before the friction. I believe the arc length from the top to the friction section is 4∏ - 0.5m. But do not know where to go from there.
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    Bullet passing through block of wood. Find max height of the wood.

    I cannot believe I did not see that. :S. Thank you.
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    What is the maximum height of the rocket?

    Homework Statement A rocket has a body which consists of 0.49kg of material. This body holds 1.47kg of fuel. The fuel is consumed at a rate of 0.49kg/s, and the exhaust speed of the fuel is 60m/s. Assuming that the rocket starts from rest, what is the maximum height the rocket reaches...
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    Bullet passing through block of wood. Find max height of the wood.

    Homework Statement A bullet of mass 0.005kg is shot at a suspended block of wood with mass 1kg. The bullet initially has a speed of 200m/s, and passes through the block of wood. The bullet passes through the wood, and 50J of work is done deforming the shape of the bullet and block. If the...
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    Mass in circular motion with friction. Find max height.

    Homework Statement A mass starts from rest at the upper rim of a semi-circle of radius 8m. In the bottom of this there is a region of size 1m which has a coefficient of kinetic friction of 0.5. What is the maximum height that the mass reaches after passing through this region once...
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    Mass in circular motion. Draw Diagram and find/explain variables.

    Homework Statement A ball of mass m is held by a string of length L and swung in a horizontal circle. The string makes an angle θ with the vertical (as shown). a. Draw a diagram clearly labeling all forces on the mass. b. Find T, the amount of time that it takes for the ball to complete...
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