A very long, straight wire carries a constant current. The magnetic field a distance d from the wire and far from its ends varies with distance d according to

A) d^-3
B) d
C) d^2
D) d^-1
E) d^-2

Mechanical energy is when the amount of kinetic and potential energies added together remains the same. conserved created lost

How does a circuit breaker protect a refrigerator? a. when the current is too high, a metal strip in the fuse melts and opens the circuit. b. when the resistance is too high , a re-settable which opens a circuit c. when the current is too high , a re-settable switch opens the circuit d. when the resistance is too high a metal strip in the fuse melts and opens the circuit

In a game of pool, ball a is moving with a velocity v0 of magnitude v0 = 15 ft/s when it strikes balls b and c, which are at rest and aligned as shown. knowing that after the collision the three balls move in the directions indicated and assuming frictionless surfaces and perfectly elastic impact (that is, conservation of energy), determine the magnitudes of the velocities va, vb, and vc.