Download For the test over magnetism, you should know:

For the test over magnetism and induction, you should know:
1. How is magnetic force related to distance between poles in Coulomb’s law
of magnetic force?
2. How is the magnetic field strength around a current carrying wire related to
distance from the wire?
3. Who showed the connection between electricity and magnetism?
4. Draw the magnetic field for a
a. simple bar magnet
b. current carrying wire.
5. What is the magnetosphere and what is its shape?
6. What is the shape of the earth’s magnetic field and how are the poles
situated?
7. What are magnetic domains?
8. How are the domains oriented in
a. non-magnetized and
b. magnetized iron?
9. What is meant by magnetic declination?
10. Name two similarities and one major difference between electric charges
and magnetic poles
11. What type of force occurs between current carrying wires when currents
are in the
a) same direction or
b) opposite directions?
12. What is a solenoid? What is the shape of its magnetic field?
13. How can the magnetic field of a solenoid be intensified?
14. What creates magnetic fields?
15. What are the units of
a. magnetic flux
b. flux density
c. inductance
16. Be able to use the three right hand rules to figure magnetic field
direction for a straight wire and a loop or coil of wire if you are given the
direction of the current.
17. What is the function of the commutator in a dc motor or generator?
18. What is a galvanometer?
19. How is the direction of the magnetic force directed on a moving charged
particle in a magnetic field found?
20. What if the charged particle is in the magnetic field but not moving?
21. Draw the path of a positively charged particle moving left to right in a
region of a uniform magnetic field (into or out of the page). How would it
be different for a negatively charged particle?
22. Under what conditions will induction occur?
23. What is Faraday’s Law?
24. What does Lenz’s law say about direction of induced current? Be
prepared to find the directions of induced currents using Lenz’s law for a
loop in a changing magnetic field or a coil with a magnet being inserted or
withdrawn. Examples:
a. a loop of wire is situated horizontally in an upward directed magnetic
field that is decreasing in strength. What is the direction of the
induced current in the loop?
b. The N pole of a magnet is withdrawn from a solenoid by pulling it
upward. What is the direction of the induced current in the solenoid,
viewed from above?
25. What type of energy conversions are taking place in motors and
generators?
26. If 2 coils are being used to show induction, with 2X as many coils in the
secondary as the primary and a battery of 3V DC is connected to the
primary, what is the secondary voltage?
27. If a transformer steps up voltage, what happens to the current?
28. Calculate the velocity of a charge given the magnetic force and the
magnetic field strength
29. Calculate the external magnetic field strength, given the current and the
magnetic force on a wire.
30. A transformer has 2500 turns in primary, 500 turns in secondary, and
120 V AC input.
a. Calculate the secondary voltage
b. If the secondary draws 1.5 A, what will be the primary current if it is
an ideal transformer?