1. Unit 8 – Magnetism and Electromagnetism

2. I. _________ explain forces ______________________________. All fields are ___________ because they have ____________. A. ___________________field Earth Measure the force of gravity F g acting on a test __________. FgFg m magnitude : gravitational field _________ g = F g / m direction : __________________ same as F g Near Earth’s surface: that act at a distance mass m Gravitational Same as _____________________ due to gravity _______________ g = -9.81 N/kg the acceleration strength vectorsdirection = -9.81 m/s 2 Fields

3. B. _____________ field: FeFe q magnitude: electric field _______________ E = F e / q direction : same as F e _________ object Measure the electric force F e acting on a _____________________________. Electric positive test charge q. charged strength

4. test _________ direction: Same as the direction that the __________ __________of the test compass points when the compass is placed in the _______ magnet C. ________________ field: magnitude: magnetic field ______________ = Magnetic compass stronger near magnet strength north pole field The equation for magnetic field strength is complicated and will not be used in this course. N S

5. 1. Any field force is ___________________to its field lines. F1F1 F2F2 F3F3 1 2 3 tangent Notes on fields: field line A ____________ compass is really a ___________________ that is _________________ on a _________________ pin. magnetic tiny magnet balanced low-friction _____ ___________ S N magnet pin

6. 3. Why do field lines never cross? 2. In the diagram below, where is the field strongest? A B At ____, because the _____________ the lines, the ____________ the field. field line 1 field line 2 F2F2 F1F1 P At point P, there would be _____ ___________ forces. B stronger closer 2 different ??

7. _______________________ of the different fields: type of field test object direction of the field is the same as the direction of the…. gravitational mass m gravitational force acting on m electric positive charge q electric force acting on the “+” q magnetic compass north pole of the compass Comparison