Electromagnetic Force Force on a Charged Particle F

Electromagnetic Force

Force on a Charged Particle F= Bqv F=force (N) q= charge (C) velocity (m/s) B= Magnetic field N/Amp∙m or Tesla

EXAMPLE An electron travels at a speed of 3 x 106 m/s through a magnetic field of 4 x 10 -2 Tesla. How much force is acting on the electron? F=Bqv F= (4 x 10 -2 T)(1. 6 x 10 -19 C)(3 x 106 m/s) F= 1. 9 x 10 -14 N

Force on a Wire With Current F=BIL F- force(N) I-current(amps) L-length(m) B- Magnetic Field (N/A∙m) or Tesla

Example A wire 1. 0 m long carries 0. 50 amps of current. If the force acting on the wire is 0. 2 N, what is the magnetic field strength the wire experiences? F=BIL 0. 20 N = B(0. 5 Amp)(1. 0 m) B = 0. 40 N/A∙m

B = 0. 4 N/A∙m I S N F =0. 20 N

Alternating current- Current that reverses direction due to a force and a magnetic field acting on a wire. *Use right hand rule F B N F C F A D S F Point (A)- Current is outward Points (B) and (D)- no current, force is parallel to field Point (C)-Current is into the wire

Graphing Alternating Current IMax 0 -I max A A B D C B D t C *Commercial frequency is 60 Hz so current changes direction 120 times per second!

Diode- Converts AC to DC by limiting the direction of the current flow I t

Graphing Direct Current I max t Doesn’t change direction

Generator-Rotating loop in a magnetic field that produce a current. Current changes direction every ½ cycle (AC). F An outside force causes the wire loop to rotate inside a magnetic field. F The current changes direction due to the loop in the wire.

Motor-Uses a current in a magnetic field to generate a force. This force allows work to be done by the motor.