Does an electric field exist in the center of a cavity inside a sphere? Can I just apply Gauss's law and say that because no charge is enclosed, the electric field is zero? If not, why can Gauss's law not be applied?
Thanks,
positron
I am having problems with the following:
A uniform 2 kg cylinder rests on a laboratory cart. The coefficient of static friction between the cylinder and the cart is 0.5. If the cylinder is 4 cm in
diameter and 10 cm in height, which of the following is closest to the minimum acceleration of...
How do you know that any image that is real is inverted and that any image that is virtual is upright, based on the equation? I know I can just memorize this fact, but is there another way to think about it?
If you place an object a distance so from a spherical mirror, how do you calculate the image location given that the image is right side up and magnified by two times? I know the equation but I always get confused about what signs to use for lenses vs. mirrors, etc.
I know the magnification...
Two blocks each of length L are piled near the end of the table. What is the maximum distance between the edge of the table and the edge of the outer block before the system topples? I understand that if the center of mass of the system must be to the left of the edge of the table for the...
When two objects collide, how do you determine which object experiences the greater change in momentum? for instance, if A and B with different masses traveling at different speeds collide, do they experience the same momentum change after the collision? What about KE?
This is my reasoning...
It be the one with the smaller moment of inertia. I for a solid cylinder of the same radius and mass as the hoops is larger, so it would go down faster. I for the solid cylinder is 1/2*M*R^2 and I for the hoops is just M*R^2. If the moment of inertia of the cube were greater than the...
A meter sticks moves with velocity 0.60c relative to an observer. The observer measures the length of the meter stick to be L. The problem states that 0.80<L<1.0 m must always be true.
So far, I have determined that
Gamma = 1/sqrt(1-0.60c^2/c^2) = 0.8.
What I don't understand is why there...
In a race down inclined plane why does a cube reach bottom first? The other object is a solid cylinder. The cylinder rolls without slipping, and the cube slides. The cylinder has radius R, and a cube has radius R. Does this depend on the mass of the objects? Is it because since the cube...
Is there an easy way to remember what kind of images will be formed from converging/diverging lens depending on where you place the object relative to the focus? For instance, how to tell if the image is inverted vs. erect, real vs. virtual, smaller vs. magnified? I always have a hard time...
There is a soap film of thickness t in air. I don't understand intuitively why a film thickness of of t = lambda/4 where lambda is the length of the light that is incident upon the film, results in maximum brightness of the light. I know that this is true from the equation for interference but...
I have a question about thse following system: block of mass M is attached to a spring is on an inclined plane.
Why do the force and energy analysis equations give different answers? The question is to find the maximum extension of the spring. Here is my thinking so far.
I know if you...
Yes, the problem is in 1-D. The potential is a general symmetric potential, so we don't know necessarily have an actual analytical solution to Schrodinger equation. So how do we know the ground state must be symmetric, and that if we put another electron in the potential, it has the same wave...
for a symmetrical potential with one electron, i know that the wavefunctions are symmetric or antisymmetric. for the ground state why is the wavefunction symmetric?
Also, if you add a second electron that is non-interacting, (why) does it have the same wavefunction as the first electron?
Consider this decay:
Pion+ -> muon+ + neutrino
It says that one can check the longitudinal polarization of the muon+ and this would confirm that the parity is not conserved. Can you explain what this means in simple terms?