Magnetic Field Strength (B)

Telsa (T) = 1 N/Am

Gauss = 10-4 T

Magnetic Force on a moving charge

FB = |q|vBSin

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B

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A charge of –q is shot into a region of E = 20,000 N/C and B = -.50T. What must be the velocity of the charge so that it is not deflected?

+q

B

v

Describe the motion of this charge

Magnetic Force on a current carrying wire

I I

FB = ILBsin

I B

L2

L1

Find the torque on this rectangular loop of wire

Magnetic Fields created by current carrying wires

I

B = 0I/(2r)

0 = permeability of free space (4 x 10-7 Tm/A)

I

e+

2 x 105 m/s

20 A

4 cm

Find the magnetic force on the proton

I1

I2

Find the magnetic force per unit length that each wire exerts on each other.

Motional EMF

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Conducting wires moving in a magnetic field

FB = qvBsin

= vBL

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Faraday’s Law of Electromagnetic Induction: The magnitude of the induced EMF is equal to the rate of change of magnetic flux through the circuit.

Magnetic Flux B = BAcos

= -dB/dt

B B

Lenz’s Law: When magnetic flux is changing, an induced current will occur to oppose the change in magnetic flux.

N N

B

A coil of wire of radius 8.4 cm is rotating in a magnetic field of 0.75 T. If it starts and an angle of 0 degrees and rotates to and angle of 45 degrees in 1.5 sec, find the magnitude of the induced voltage. What direction will the current flow in the wire?

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A charge of q is shot into a region of E = 15000 N/C and B = .85T. What must be the velocity of the charge so that it is not deflected?

I1

I2

Find the magnetic force per unit length that each wire exerts on each other.

V d = 7.5 cm

A conducting wire is moving with a velocity of 0.35 m/s in a magnetic field of 0.90 T. Find the magnitude of the induced EMF and the electric field. Determine the direction of the electric field

B

I

Determine the direction that this loop of wire will spin.

I = 12A

Determine the magnitude of the magnetic field generated by the wire below at a point 6.5 cm from the wire. Make a sketch to indicate the direction of the magnetic field.