A spring is hung from the ceiling. A 0.353-kg block is then attached to the free end of the spring. When released from rest, the block drops 0.165 m before momentarily coming to rest, after which it moves back upward. (a) What is the spring constant of the spring? (b) Find the angular frequency of the block's vibrations. (a) Number Units (b) Number Units
The figure shows a particle with positive charge q = 6.40×10−19 C moving with speed v = 8.08×103 m/s toward a long straight wire with current i = 369 mA. At the instant shown, the particle's distance from the wire is d = 1.29 cm. What is the magnitude of the force on the particle due to the current? Number Units
A proton travels through uniform magnetic and electric fields. The magnetic field is in the negative x direction and has a magnitude of 2.22 mT. At one instant the velocity of the proton is in the positive y direction and has a magnitude of 2400 m/s. At that instant, what is the magnitude of the net force acting on the proton if the electric field is (a) in the positive z direction and has a magnitude of 4.39 V/m, (b) in the negative z direction and has a magnitude of 4.39 V/m, and (c) in the positive x direction and has a magnitude of 4.39 V/m?
Two 4.70 kg balls are attached to the ends of a thin rod of length 70.0 cm and negligible mass. The rod is free to rotate in a vertical plane without friction about a horizontal axis through its center. With the rod initially horizontal (see the figure below), a 17.0 g wad of wet putty drops onto one of the balls, hitting it with a speed of 1.16 m/s and then sticking to it. (a) What is the angular speed of the system just after the putty wad hits? (b) What is the ratio of the kinetic energy of the system after the collision to that of the putty wad just before? (c) Through what angle (in degrees) will the system rotate before it momentarily stops? (a) Number Units (b) Number Units (c) Number Units
The frequency of oscillation of a certain LC circuit is 167 kHz. At time t = 0, plate A of the capacitor has maximum positive charge. At what earliest time t > 0 will (a) plate A again have maximum positive charge, (b) the other plate of the capacitor have maximum positive charge, and (c) the inductor have maximum magnetic field? (a) Number Units (b) Number Units (c) Number Units
In the figure, set R = 261 Ω, C = 59.7 μF, L = 236 mH, fd = 60.0 Hz, and εm = 8.86 V. What are (a) Z, (b) φ, and (c) l? (a) Number Units (b) Number Units (c) Number Units
A single spring with a 0.75 kg mass on it is stretched out and then released. Then the velocity of the mass is measured as the spring passes through its equilibrium position. This experiment is repeated 18 times; pulling the spring to a different distance each time. The amplitudes and speeds are listed below. Calculate the spring constant of the spring and give uncertainty so that you can be 95% sure that the true value of the spring lies within the range you give. k = 4 ±60 N/m Now calculate the spring constant and give uncertainty so that you can be 95% sure that the spring constant calculated from any single performance of the experiment (as opposed to doing it multiple times as above) will fall within the range given. k = 40 N/m
Consider the two charges in the figure, which are moving in opposite directions and located a distance 1 cm on either side of the origin of the given coordinate system. Charge one is 14.5 μC and is moving at a speed 17.5×106 m/s, and charge two is −5.5 μC and is moving at a speed of 4.5×106 m/s. Notice that the positive z-direction in this figure is directed out of the page.
Two friends, Burt and Ernie, are standing at opposite ends of a uniform log that is floating in a lake. The log is 3.3 m long and has mass 220 kg. Burt has mass 33.5 kg and Ernie has mass 36.0 kg. Initially the log and the two friends are at rest relative to the shore. Burt then offers Ernie a cookie, and Ernie walks to Burt's end of the log to get it. Part A Relative to the shore, what distance has the log moved by the time Ernie reaches Burt? Neglect any horizontal force that the water exerts on the log and assume that neither Burt nor Ernie falls off the log. Express your answer with the appropriate units. Submit Request Answer