Aconducting bar slides without friction on two parallel horizontal rails that are 50 cm apart and connected by a wire at one end. the resistance of the bar and the rails is constant and equal to 0.10 ω. a uniform magnetic field is perpendicular to the plane of the rails. a 0.080-n force parallel to the rails is required to keep the bar moving at a constant speed of 0.50 m/s. what is the magnitude of the magnetic field?

The lights used by mark watley (played by matt damon) during the film the martian seem to be metal halide lamps. metal halide lamps are filled with vaporized mercury and metal-halogen compounds. when an electric current is passed through the lamp, the tube begins to glow a bright white/blue color. if you were to pass this light through a prism to separate the individual light frequencies, you would see a rainbow just as you would if using natural sunlight because of the complexity of the metal halide gas and the vast amount of possible electron transitions. (the study of light in this way is known as spectroscopy and allows astronomers to know exactly what atoms compose distant stars, simply by looking at the light they emit. the spectral lines an atom produces uniquely identifies that atom just like a fingerprint uniquely identifies a person. the momentum equation and energy equation that we have used above can be combined to give the following equation: c = e p where again p is the phonon momentum, e is the photon energy and c is the speed of light. when you divide the photon energy found in #6 by the photon momentum found in #4, do you get the speed of light? (if not, check your work for questions #4 through #6). yes no

Alfred pushes on a heavy box, but cannot move it. the box has a lot of inertia motion friction gravity

Awave with a frequency of 500 hz is traveling at a speed of 100 m/s.what is the wavelength?