A spherical capacitor is formed from two concentric sphericalconducting shells separated by vacuum. The inner sphere has radius10.0 centimeters, and the separation between the spheres is 1.50centimeters. The magnitude of the charge on each sphere is 3.30nanocoulombs.1)What is the magnitude of the potential difference DeltaV between the two spheres?2)What is the electric-field energy stored in the capacitor?

How many seconds does it take a pebble released from rest off a bridge to fall 29.4 m ? what is the pebble's speed when it has fallen 29.4 m ?

Search coils and credit cards. one practical way to measure magnetic field strength uses a small, closely wound coil called a search coil. the coil is initially held with its plane perpendicular to a magnetic field. the coil is then either quickly rotated a quarter-turn about a diameter or quickly pulled out of the field. (a) derive the equation relating the total charge q that flows through a search coil to the magnetic-field magnitude b. the search coil has n turns, each with area a, and the flux through the coil is decreased from its initial maximum value to zero in a time ∆t. the resistance of the coil is r, and the total charge is q = i∆t, where i is the average current induced by the change in flux. (b) in a credit card reader, the magnetic strip on the back of a credit card is rapidly “swiped” past a coil within the reader. explain, using the same ideas that underlie the operation of a search coil, how the reader can decode the information stored in the pattern of magnetization on the strip. (c) is it necessary that the credit card be “swiped” through the reader at exactly the right speed? why or why not?

Four friends, a, b, c, and d are standing varying distances away from a speaker which is producing sound waves.