1. Chapter 14 Lesson 2 Answers to Blue Review

2. How are all magnets alike? How are they different?
All magnets attract certain metals, especially iron or steel. They do not attract some metals and materials such as plastic or wood. Magnets differ in size, shape, strength, and uses.

3. How are a magnet and electromagnet alike? How are they different?
Alike: Both are magnets; they attract iron and some other metals. Different: Electromagnets have a magnetic field only when the current is on, but permanent magnets are magnetic on their own.

4. How are a magnet’s magnetic force and magnetic field different?
A magnetic field is the area around a magnet where magnetic forces act.

5. How are a generator and motor alike? How are they different?
Alike: A generator and a motor both use a turning motion, magnets, and coils. Different: A generator uses motion to make electric current. A motor uses electric current to make motion.

6. How are a videotape and a computer hard drive alike?
They are electromagnetic recording devices. Electrical signals are saved as varying degrees of magnetism on a surface. They are later decoded as magnetic forces and turned back into electrical signals.

7. Lesson 3 Blue Review Answers

8. What are the two main differences between potential and kinetic energy?
Unlike kinetic energy, potential energy does not involve motion and comes in many forms.

9. What is hydroelectric power?
It is electricity generated by falling water, usually water trapped behind a dam.

10. What is geothermal power?
It is the use of Earth’s heat to make electricity.

11. What is solar power?
Solar power is energy from the sunlight that is harnessed to meet energy needs.