On pages 784-786 you will find a practice test - this is a great study guide for you! You do not need to know how to answer 13, 14, 15, 19-22. The answers are below.
If you need extra help, I'll be in early tomorrow morning.
Practice Test Answers:
1) d, 2) b, 3) a, 4) b, 5)d, 6)b, 7)d, 8)d, 9)b, 10)a, 11)a, 12)d
16) As the loop rotates, it will generate a maximum voltage and maximum induced current when it cuts perpendicularly through the field lines. Assume the plane of the coil starts parallel with the faces of the north and south poles of the magnet. As the loop rotates 90 degrees, the voltage and current with go to a maximum. When the loop to the 180 position, no field lines will be cut and hence, the induced current and voltage will be zero. The same cycle will happen at 270 degrees and then back to the original position. The graph should look like this:
17) A simple galvanometer consists of a coil of wire wrapped around a compass. As current flows through the coil, the compass deflects from its normal position to line up with the magnetic field of the coil.
18) a. Electromagnets can pick up mainly iron and steel
b. When the electromagnet has the current turned off, it stops being a magnet, and the steel or iron will drop.
c. The soft iron core is made from thousands of small metallic crystals called domains. Each domain is magnetic, but the point in random directions so there is no net magnetic effect. When an external magnetic field is supplied to the soleniod, many of the domains line up with the solenoid's field, increasing its strength tremendously.
