Ametal disk of radius 4.0 cm is mounted on a frictionless axle. current can flow through the axle out along the disk, to a sliding contact on the rim of the disk. a uniform magnetic field b= 1.25 t is parallel to the axle of the disk. when the current is 5.5 a, the disk rotates with constant angular velocity. what's the frictional force at the rim between the stationary electrical contact and t?

The speed of sound in ice, water, and steam is shown. what best explains the speed of sound in different states of matter? sound travels fastest in ice because energy is easier to transfer when the molecules are close together. sound travels slowest in steam because the sound has to move around the gas molecules that are far apart. sound travels fastest in ice because the temperature of solids is always greater, so the heat transfers the sound energy. sound travels slowest in steam because the pressure is so great the sound cannot travel though the steam particles.

4. if you were an astronaut on the moon, what would you experience? what would you see from your perspective?

What causes the formation of ocean currents?