hw3_p5406_s07 - U = R as dV A J Show that the change in...

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
HW 3 Phys5406 S07 due 2/8/07 1)JDJ 4-13 2)A uncharged, conducting sphere of mass M and radius R floats with 1/4 of its volume submerged in a dielectric liquid of permitivity ± . When a total free charge Q is put on the sphere it floats with 1/2 its volume submerged. Calculate, the Q = f ( ±, R, M ) needed. 3) Suppose a conducting sphere of radius R is cut through a diameter into two hemispheres. The hemispheres are glued together and a charge Q is placed on the sphere. How much force must the glue withstand to keep the hemispheres from pulling apart. 4)Start with the expression for the magnetic potential energy for a non-linear system,
Background image of page 1
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: U = R as dV A · J . Show that the change in energy δU for a small change in J is, δU = Z as dV B · δ H . 5) Suppose a long solenoid of n turns/length, radius R and current I. Consider a screw driver (approximated as a cylinder with radius a such that a << R ) of permeability μ partially inside the solenoid and partially outside at one end. The axis of the cylinder is parallel to that of the solenoid. What is the approximate force/area exerted on the screw driver? Is the latter pulled in or expelled? 1...
View Full Document

{[ snackBarMessage ]}

Ask a homework question - tutors are online