Name__________________________ Date _________________ Core ____ Physical Science Study Guide KEY

1. What factors affect the strength of gravity? Mass and distance affect the strength of gravity. If two objects are heavier then their gravitational pull will be greater. The same holds true if two objects are far apart. 2. List some conductors and insulators. What are their properties?

In a conductor, electric currents can flow freely. Electrons move quickly through these materials. Good examples of these are iron and copper. In an insulator, electric currents cannot flow freely. Electrons do not move freely through these materials. Good examples of these are plastic and wood.

3. What are the laws of attraction and repulsion?

4. Describe how magnetic forces relate to electric forces. (Hint: think about your electromagnet and how it worked)

Both magnetic and electric forces influence the motion of charged particles. Both have field lines. Both can be made stronger or weaker and both have positive and negative charges. 5. How can you make an electromagnet stronger?

One can make an electromagnet stronger by increasing the voltage, increasing the coils, placing the coils closer together and using thicker wire or a better conductor.

6. What components make up a circuit? The components that make up a circuit are wires, a power source, a bulb and a switch (optional).7. Provide an example of static electricity. (Look up John Travoltage on

PHET Colorado Simulations in case you forgot!)

Balloon rubbed on hair creates a buildup of charges on balloon. When the balloon sticks to the wall, the positive charges will be attracted to the negative charges.

8. What are the properties of waves?

The properties of waves are amplitude, wavelength and frequency.

9. Draw a wave. Show amplitude, frequency and wavelength.

10. Why is digital technology superior to analog technology? Digital technology is superior to analog due to the following reasons. Digital information is encrypted so information is sent through a binary code making it more secure. Digital lasts longer than analog. It can hold more information and it can be edited. Digital also has better sound quality, less interference and static.

11. How does light and sound interact with matter? Is there a difference?

(think about how light and sound travel in outer space as compared to on earth.)

Light interacts with matter in that it doesn't need a medium to travel in. Sound does require a medium. For this reason, light travels faster than sound. So in space, sunlight can reach Earth even though there is no matter (air etc.) for it to travel through. If sound is made in space, no one would be able to hear it.

12. What are three differences between FM and AM? FM radio is transmitted through frequency, uses million Hz and the signals are fixed.AM radio is transmitted through amplitude, measured in thousand Hz, and the signals are not fixed (they are varied.).

13. What is the law of conservation of energy?

14. How is heat transferred? Provide an example. Heat is transferred by conduction, convection and radiation.

15. Describe an example that includes at least three energy conversions.

Cat pushes door open (mechanical), door hits shelf (sound), books on shelf fall on clock (sound), light turns on (light, electric)

16. Define conduction and radiation (advanced: convection also). Conduction- heat transfer by TOUCHING

Radiation- heat transfer by infrared waves (electromagnetic radiation).Convection- heat transfer in liquids (air or water). Energy is carried by fluid from one place to another.

17. What is the difference between potential and kinetic energy? Use a pendulum to explain this.

Greatest potential energy is at the highest point of the swing.

Greatest kinetic energy is at the bottom of the swing.