Grade+7-Test+Review+-+Answers

=Grade 7 – Review for Electricity and Magnetism – ANSWER KEY =

1. A(n) __ ** CIRCUIT ** __ is a closed path that an electric current can follow. 2. In a(n) __ ** CONDUCTOR ** __, electric charges can move easily. 3. A_ ** PARALLEL  ** _ circuit has more that one path for electric current to follow. 4. An object that does not contain equal amounts of positive charge and negative charge has a(n) _ ** STATIC  ** **  CHARGE  ** 5. A(n) __ ** CURRENT ** __ is the flow of electric charges. 6. _ ** VOLTAGE  ** _ is a measure of the energy electrons transfer to a circuit as they flow. 7. A(n) __** ELECTROMAGNET **__ is made of a current-carrying wire wrapped around an iron core. 8. A measure of how difficult it is for current to flow in an object is its ___** RESISTANCE **___ 9. What type of energy conversion occurs inside a battery? _** CHEMICAL ** __energy to__ _** ELECTRICAL ** __energy__ 10. Every electric charge is surrounded by an __** ELECTRIC FIELD **___ 12. Increasing the voltage in a circuit increases the _** ENERGY TRANSFERRED_ ** in a circuit? 13. The magnetic force between two magnets will repel if the poles are __ ** ALIKE **_ ____ and attract if the poles are __ ** DIFFERENT  **__ _ __ 14. After electrons are transferred from glass to silk, which of the following is true about the glass and silk? __** THEY ATTRACT EACH OTHER. **__ 15. Which type of material makes a good electrical conductor? __** METALS LIKE COPPER, SILVER, ETC. **__ 16.Bringing your negatively-charged hand near a doorknob charges the doorknob by ** INDUCTION **_ 17. If an object is positively charged, then it has more ** PROTONS ** __than__ ** ELECTRONS **__.__ 18. What energy conversion takes place in a generator? ** MECHANICAL ** __to__ ** ELECTRICAL **_ 19. What type of atomic particle does not have an electric charge? __ ** NEUTRON **_ __ __** 20. ** An object is electrically charged if the amounts of positive and negative charge it contains are not _** EQUAL **_. __ __ 21. ___** INSULATORS ** __are materials in which electric charges do not move easily.__ __ 22. Lightning occurs when the __** STATIC CHARGE ** on a storm cloud causes charging by induction on the ground or another cloud. 23. A spark between your hand and the doorknob is an example of an __ ** ELECTRIC DISCHARGE ** __ __ 24. What causes current to flow in a wire? ** ELECTRIC CIRCUIT ** __ __ 25. Which of the following energy conversions occurs inside a battery?** CHEMICAL TO ELECTRICAL ** __ __ 26. The measure of how difficult it is for electrons to flow in an object is called the __** ELECTRIC RESISTANCE ** 27. Increasing the voltage in a circuit increases the __ _** IT INCREASES THE ELECTRIC CURRENT **. __ __ 28. A(n) __** SERIES CIRCUIT ** __circuit has only one path for current to follow.__ __ 29. A(n) __** ELECTROMAGNET **_ is made of a current-carrying wire wrapped around an iron core. 30. A group of atoms that have their magnetic poles pointing in the same direction is called a(n) _ ** MAGNETIC DOMAIN  ** _. 31. Which of these does a simple generator rotate to produce current? ** A WIRE LOOP  ** 32. Electrical current is measured in __ ** AMPERES ** __. 33. Electrons have a __ ** NEGATIVE **_ charge? __ __ 34. Voltage measures __** THE ENERGY ELECTRONS HAVE **_. 35. Feeling a shock from a metal door handle is an example of an _ ** ELECTRICAL DISCHARGE  **. 36. A __ ** PARALLEL  ** _ circuit has multiple paths for current flow. 37. Ohm's law states that _ ** VOLTAGE  ** _, **  CURRENT, AND RESISTANCE are related ** 38. What flows in an electric circuit? ** ELECTRONS  ** 39. How do insulators and conductors differ? 40. As voltage increases, what happens to current? ** IT INCREASES. **
 * 11. ** In a permanent magnet, the domains are _** LINED UP _**
 * INSULATORS DO NOT ALLOW ELECTRONS TO PASS THROUGH THEM EASILY AND CONDUCTORS LET THEM MORE EASILY. **