Recent content by smhippe

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    Molecular movement, potential energy and angular frequency

    Sorry about that, I'm trying to avoid using the equation editor... (A/r^12)-(B/r^6) Hopefully that makes some more sense.
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    Car braking and ratio of force of friction

    That means I have to find the normal force on each tire first then right? I can do this by using the FBD and substituting?
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    Car braking and ratio of force of friction

    Homework Statement The front brake pads on your car wear out faster than the rear brake pads; in fact, some cars are specifically designed with large front brake pads because of this. This results from the fact that when a car is braking the magnitude of the friction force acting on the...
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    Molecular movement, potential energy and angular frequency

    Homework Statement The relative motion of two atoms in a molecule can be described as the motion of a single body of mass m = 3 x 10-26 kg moving in one dimension, with a potential energy given by the equation U(r)=(A/(r^12))-(B/(r^12)) n this equation A = 10^10 J m^12 and B = 10^20 J m^6 are...
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    Spring and maximum compression time

    Try #2 So from momentum conservation i got the velocity of both blocks to be 10.46 just before they hit the spring. Using that I got the distance that the spring compressed by .5*m*(v^2)=.5*k*(x^2) and got x to be 4.5m. Then using that I used F=-kx=ma and got a=-24.23. From there I just used a...
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    Spring and maximum compression time

    Okay so I can plug it into momentum conservation laws to find what the velocity of the combined blocks is. But, does that mean that I can still use energy conservation to figure out how far the spring is compressed after the collision? (I mean 1/2*m*(v^2)=1/2*k*(x^2))
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    A person jumps on a merry go round, how much does the merry weigh?

    Homework Statement A person with a mass of 52 kg runs with a speed of 6.8 m/s jumps onto the outer rim of a merry-go-round. The merry-go-round has a radius of 1.5 m and can be modeled as a large disk. The merry-go-round was initially at rest before the person jumped onto it and rotates at...
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    Spring and maximum compression time

    Homework Statement A mass m1 = 8 kg is at rest on a frictionless horizontal surface and connected to a wall by a spring with spring constant k = 70 N/m as shown in the figure. A second mass m2 = 5 kg is moving to the right at vo = 17 m/s. The two masses collide and stick together. How long...
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    Opposing spring oscillation with mass

    Homework Statement A 36 kg mass is placed on a horizontal frictionless surface and then connected to walls by two springs with spring constants k1 = 3 N/m and k2 = 4 N/m. What is the frequency, f (in Hz), of oscillation for the 36 kg mass if it is displaced slightly to one side...
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    Pendulum and spring oscillation

    Homework Statement A 5 kg sphere is connected to a thin massless, but rigid rod of length L = 1.3 m to form a simple pendulum. The rod is connected to a nearby vertical wall by a spring with spring constant k = 75 N/m, connected to it at a distance h = 1.1 m below its point of...
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    What is the total work required to drive a screw into a block of wood?

    Well, the equation for how it increases is just .6*(rotation number). The average torque would be the maximum and minimum divided by two...The maximum is obviously 12 so would that make the minimum be 0? That doesn't really make sense though. In that case the average would be 6. The equation for...
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    Calculating Forces on a Cantilever: Physics Homework Problem

    Homework Statement A 3 m long cantilever with a mass of 250 kg is attached to a wall and also held in place by a steel cable that is attached to the far end of the cantilever at an angle of 30° with respect to the cantilever as shown in the figure at right. A 5 kg mass also hangs from...
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    What is the total work required to drive a screw into a block of wood?

    Homework Statement It takes 20 turns to drive a screw completely into a block of wood. Because the friction force between the wood and the screw is proportional to the contact area between the wood and the screw, the torque required for turning the screw increases linearly with the...
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    Which Spring Has a Larger Displacement?

    Spring B. That's what my gut feeling was. So if I understand everything correctly we don't need to know equilibrium length. If we were to actually solve this problem would we need it then?
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    Which Spring Has a Larger Displacement?

    Homework Statement An 8 kg mass is hanging from two springs that are attached to the ceiling as shown in the figure. The spring constant of spring A is 165 N/m and the spring constant of spring B is 123 N/m. Which spring has a larger displacement? Note: Spring A is attached to the ceiling on...
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