Download May 22B_day34.notebook

May 22B_day34.notebook
May 22, 2012
Check for understanding
Draw the charging curve for the capacitor in the circuit shown calculate the amount of charge after 2ms in terms of Q
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May 22B_day34.notebook
May 22, 2012
HW Planner
ADD Regents review assignment due next WEDNESDAY showing all work...
Video Projects DUE May 31st !!!
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May 22B_day34.notebook
May 22, 2012
Magnetism
• Magnets have north and south poles and ALWAYS come in PAIRS
• Like charges and electric fields, N and S poles set up magnetic field lines around them
• Magnetic field lines are VECTORS
• Magnetic fields are called B fields and are measured in Teslas
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May 22B_day34.notebook
Magnetic field lines
May 22, 2012
Tesla = Weber/meter2
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May 22B_day34.notebook
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Magnetic Force on moving charges
F = qvBsinθ
q = charge v = velocity of particle B = magnetic field
θ = angle between motion and B field
Max = Min = proton passing between poles of horseshoe magnet
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May 22B_day34.notebook
May 22, 2012
Hand Rules!
Conventional current (positive charge flow)
Right hand rule
THUMB always points the direction of current or charge in motion
Curl of fingers for B
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May 22B_day34.notebook
May 22, 2012
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May 22B_day34.notebook
May 22, 2012
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May 22B_day34.notebook
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May 22B_day34.notebook
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An electron moves across the Earth's equator at a speed of 2.5 X 106m/s in a direction of 35o N of E. At this point, the Earth's magnetic field has a direction of due North and is parallel to the surface and has a magnitude of 0.10 X 10­4 T. What is the force acting on the electron due to its interaction with the Earth's magnetic field?
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May 22B_day34.notebook
May 22, 2012
A wire of length 0.50m carries a current of 0.10A in the positive X direction, parallel to the ground. If the wire has a weight of 1.0 X 10­2N, calculate the minimum magnitude of the magnetic field that exerts a magnetic force on the wire equal to the wire's weight?
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May 22B_day34.notebook
May 22, 2012
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