3. Physics Practice Questions- Chapter 24

moving electric charge.

1) The source of all magnetism is

a magnetic field. an electric field.

10) Surrounding every moving electron is

move around the nucleus. spin on their axes.

11) Magnetism is due to the motion of electrons as they

iron

12) Magnetic domains normally occur in

circle the wire in closed loops.

13) Magnetic field lines about a current-carrying wire

perpendicular to the magnetic field direction.

14) The force on an electron moving in a magnetic field will be the largest when its direction is

poles

15) The intensity of cosmic rays bombarding the Earth's surface is largest at the

Australia.

16) If we think of the Earth as a magnet, its north (-seeking) pole is nearest

north pole

17) Which pole of a compass needle points to a south pole of a magnet?

magnetic sensors in their heads.

18) Pigeons navigate primarily by

exactly 100 N.

19) Magnet A has twice the magnetic field strength of Magnet B and at a certain distance pulls on magnet B with a force of 100 N. The amount of force that magnet A exerts on magnet B is

pigeons, then Chinese.

2) Magnetic compasses apparently were first used by

equally huge.

20) Compared to the huge force that attracts an iron tack to a strong magnet, the force that the tack exerts on the magnet is

is deflected into the plane of the page.

21) An electron is shot from the right, toward a spot just between the ends of the magnet. The electron

hardly at all.

22) If a compass is moved from the northern hemisphere to the southern hemisphere, its magnetic needle will change direction

moving charges in the liquid part of the Earth's core. great numbers of very slow moving charges in the Earth. convection currents in the liquid part of the Earth's core.

23) A possible cause for the existence of the Earth's magnetic field is

north to south

24) Outside a magnet, magnetic field lines are conventionally drawn from

electric field

25) Which force field can increase a moving electron's speed?

magnetic field

26) Which force field can accelerate an electron, but never change its speed?

at most half as strong as the original magnet.

27) When a bar magnet is broken in two as shown, each piece is

exist now

28) Superconducting electromagnets

an electric field. a magnetic field.

3) Moving electric charges will interact with

at right angles to the direction of the motion.

4) If a steady magnetic field exerts a force on a moving charge, that force is directed

at right angles to the direction of the field.

5) If a steady magnetic field exerts a force on a moving charge, that force is directed

the net spins of its electrons are in the same direction.

6) An iron rod becomes magnetic when

attract.

7) Like kinds of magnetic poles repel while unlike kinds of magnetic poles

north pole.

8) Several paper clips dangle from the north pole of a magnet. The induced pole in the bottom of the lowermost paper clip is a

north or south pole - no difference really.

9) An iron nail is more strongly attracted to the