Chapter 5.6

Question 1

What does any moving charge create?

Answer 1

-it creates a magnetic field

Question 2

What are the two ways a magnetic field is created?

Answer 2

• a moving individual charge such as an electron

- or the movement of charge in the form of current through conductive material such as a copper wire

Question 3

What is the unit for magentic field strength

Answer 3

• it is a Tesla

- 1 Tesla = 10^4 gauss

Question 4

What is the difference between ferromagnetic materials and paramagnetic materials

Answer 4

• they both have unpaired electrons
• > and permanent atomic magnetic dipoles that are normally oriented randomly so that the material has no net magnetic dipole
• unlike paramagnetic materials
• > ferromagnetic materials will become strongly magnetized when exposed to a magnetic field or under certain temperatures
• > paramagnetic materials only become weakly magnetized when exposed to a magnetic field
• paramagnetic include aluminum, copper and gold
• ferromagnetic include iron nickel and cobalt

-the key difference between them comes down to the strength of magnetization

Question 5

What are example of ferromagnetic materials

Answer 5

-nickel, iron and cobalt

Question 6

What hand rule is used for the direction of a magnetic field created by a straight wire

Answer 6

• use the right hand rule
• thumb is in the direction of the current
• wrap fingers around the current carrying wire
• > fingers mimic the circular field lines curling around the wire

Question 7

What are the differences between the magnetic field equations of a straight wire and that of a circular one

Answer 7

Straight wire
->magnitude of a magnetic field at any perpendicular distance, r, from the current carrying wire

Circular wire
->magnetic field only at the center of the circular loop with a radius r

Question 8

What is meant by the term Lorentz force?

Answer 8

-it is the sum of electrostatic and magnetic forces

Question 9

How do you determine the direction of a magnetic force on a moving charge

Answer 9

• use the right hand rule
• thumb is the moving charge direction(so the velocity direction)
• the fingers are in the direction of the magnetic field lines
• > palm will point in the direction of the force vector for a positive charge
• > back of the hand will point in the direction of the force vector for a negative charge

Question 10

What is a way that magnetic force is created?

Answer 10

-one needs an en external electric field acting on a charge moving in any direction