Cylindrical capacitors: An air-filled capacitor is formed from two long conducting cylindrical shells that are coaxial and have radii of

Force on moving charges: A charge is accelerated from rest through a potential difference V and then enters a uniform magnetic field oriented perpendicular to its path. The field deflects the particle into a circular arc of radius R. If the accelerating potential is tripled to 3V, what will be the radius of the circular arc?

Power: A 1500-W heater is connected to a 120-V line. How much heat energy does it produce in 2.0 hours?

Lenz’s law: In the figure, a straight wire carries a current I. The wire passes through the center of a toroidal coil. If the current in the wire is quickly reduced to zero, the induced current through the resistor R is

Self-inductance: At what rate would the current in a 100-mH inductor have to change to induce an emf of 1000 V in the inductor?

Spheres of charge: A conducting sphere is charged up such that the potential on its surface is 100 V (relative to infinity). If the sphere’s radius were twice as large, but the charge on the sphere were the same, what would be the potential on the surface relative to infinity?

Ohm’s law: When a voltage difference is applied to a piece of metal wire, a

Refraction at a curved surface: A fish appears to be 2.00 m below the surface of a pond when viewed almost directly above by a fisherman. What is the actual depth of the fish? (nwater = 1.33)

Refraction at a curved surface: A fisherman in a stream 39 cm deep looks downward into the water and sees a rock on the stream bed. How deep does the stream appear to the fisherman? The index of refraction of the water is 1.33.

Thin lenses: An optical system comprises in turn, from left to right: an observer, a lens of focal length +30 cm, an erect object 20 mm high, and a convex mirror of radius 80 cm. The object is between the lens and the mirror, 20 cm from the lens and 50 cm from the mirror. The observer views the image that is formed first by reflection and then by refraction. What is the position of the final image, measured from the mirror?