Recent content by RobL14

Homework Statement Consider a water pipe that tapers down from a diameter d_A = 5.0 cm at end A to a diameter d_B = 2.5 cm at end B. At each end a vertical pipe that is open to the air at the top is attached to the pipe. Assume that water flows through the pipe at high enough pressure that the...

Thanks, I now understand how friction is linearly accelerating the wheel. But what's wrong with my math? Shouldn't I just reach the same conclusion?

The work done by friction is equal to the energy released as heat. Calculate the work done by friction using conservation of energy, then go from there.

Thank you for helping. It's still weird to me, but let me put it another way, and you can tell me if I'm thinking about it correctly. When the net torque is zero, the wheel will spin with some constant velocity. At the same time, the wheel will translate with a linear acceleration proportional...

Oh, I think I understand what's happening here. It was staring me in the face. "Lay rubber" means to "peel-out" or essentially have your tires move without rolling, i.e. the angular velocity times the radius is faster than the velocity of the center of mass. If the torques add to zero, then...

What do you have available? Gamma radiation is high-frequency radiation that a) is dangerous to produce and b) relatively difficult to produce. I don't know how much your professor/teacher wants you exposing your class to harmful radiation.

Your initial L is correct as far as I can tell. It is your final L that is the problem. The new moment of inertia is not simply (m+M)r2. Treat the person as a point particle, which will have the same final angular velocity as the disk, whose moment of inertia is the same. You treat them...

Okay, so you found the time t that it'd take for the diver to reach y = 0. Now you need to find some horizontal velocity in the x-direction that let's him clear the ledge x = 6.06m in that time, t = 2.6s.

The weight of the parachutist doesn't really exert a torque on the system about the rotation axis. Why? The force vector points perpendicularly into the disk, so there is no component of his weight that contributes to rotational torque about that central axis. The key to this problem is angular...

Understanding "Peel-Out" From a Torque/Rotational Dynamics Perspective I've been having a lot of trouble understanding rotational dynamics involving wheels. I understand the simple stuff, but I don't understand the concepts behind the more difficult problems. Let me make this clear: this...