Which of the following magnetic devices does not carry a transport current? a. A solenoid b. The outer molten shell of the earth's inner iron core. c. A long, straight, conducting loop O d. A toroid O e. A bar magnetic made of iron.

what happens to the compass needle as you move the compass around? A. The compass needle always points north. B. the compass needle points in random directions c. the compass need;e follows the pattern of magnetic field lines.  d.the compass needle's north pole always points to the north pole of the magnet

8. An ideal solenoid having 200 turns and carrying a current of 2.0 A is 25 cm long. What is the magnitude of the magnetic field at the center of the solenoid? (Mo 4 x 10-7 T m/A) = E R % 5 www a

12. How much current must flow through a long straight wire for the magnetic field strength to be 1.0 mT at 2.0 cm from a wire? (40=4xx 10-7 T m/A) A. 9.2 A B. 16 A C. 50 mA D. 100 A

How many turns of a coil are necessary to produce a 0.25-T magnetic field inside a 50-cm-long solenoid that carries a current of 20 A?   a. 1,000 turns   b. 4,000 turns   c. 5,000 turns   d. 2,000 turns   e. 3,000 turns

5. A search coil consisting of N turns of wire in a circle of radius r is used to measure small magnetic fields. It is to be designed so that flipping it 180 degrees in a field of B=2.0 Gauss causes a total charge of Q = 1x10-7 C to pass through a ballistic galvanometer. (a) Suppose that the coil has a resistance N Ro where Ro is the resistance in one turn of wire. Using the fact that & = -do/dt, show that while the current in the coil depends on the speed with which it is rotated, the total charge Q passing through coil from start to finish does not. (b) If the resistivity of the wire is 8x10-7 m and the diameter of the wire is 100 um, what should be the radius r of the coil? (Neglect the resistance of the galvanometer.) I Gaus. N turns Ballstic Galvenometen (measunee Q)

When a magnet is passed through a conducting wire coil, the changing magnetic flux will induce     A. an electromagnetic force in the coil.     B. a neutral charge on the Faraday Ice Coil.     C. a positive charge on the Faraday Ice Pail.     D. a negative charge on the Faraday Ice Coil.

23. A 1000-kg car moves west along the equa- tor. At this location Earth's magnetic field is 3.5 × 10-5T and points north parallel to Earth's surface. If the car carries a charge of −2.0 × 10¯³ C, how fast must it move so that -3 the magnetic force balances 0.010% of Earth's gravitational force exerted on the car?

12.     A proton moving east at 2.64 x 10^5 m/s moves through a magnetic field of 2.55 x 10^-6 T to the north. What is the magnitude and direction of the force that the proton experiences?

10. A square coil that has 16.5 cm on each side containing 17 loops lies flat on your desk as shown on this page. A uniform magnetic field of magnitude 5.30 × 10-5 T points towards the left of this page. If a 6.50-A clockwise current flows through the coil, (a) determine the torque on the coil. N.m silo čcil6 ceil6 ccilo co x16 cci16 cci16 cci16 cci16 cci16 e (b) which 00 о edge of the coil rises upp 16 ccil6 ccil6 ccil6 ccil6 ccil6 cci16 ecilo Left Top None of these Bottom 16 ceil6 ccil6 cci 16 cci16 ceil6 cci16 Right ci16 cci16 cci16 cci16 cci16 eź №6 cci16 cci16 cci16 cci16 cci16 cei ceil6 ccil6 ccil6 cci16 co