1. Circuits Home

3. Which circuit is built so that if one lightbulb goes out, the other three lightbulbs will continue to glow? 54 If this one goes out The others go out. If this one goes out The other three bulbs will continue to glow. This is a parallel circuit. F, G, H above are series circuits. Home

5. Which switch, if opened, will cause the light bulb to stop glowing? F Q G R H S J T 32 If R was opened/off, the electricity would still go through S to the bulb. If S was opened/off, the electricity would still go through R and T to the bulb. If T was opened/off, the electricity would still go through S to the bulb. Battery If Q was opened/off, the electricity would NOT make it to the bulb. Home

6. How much current is flowing through this circuit? A 0.32 A B 3.1 A C 4.0 A D 12.5 A 47 Current = 4 ÷ 12.5 Home

7. What is the current in a copper wire that has a resistance of 2 ohms and is connected to a 9-volt electrical source? F 0.22 amp G 4.5 amps H 11.0 amps J 18.0 amps 46 Frequency = voltage ÷ resistance(ohms) ? = 9 ÷ 2 Current (frequency) Home

8. Energy transformation Home conservation of energy convection, conduction, and radiation energy sources Back to energy

9. Assuming the chart contains all energy transformations in the Earth system, how much solar radiation goes toward evaporating water? F 40,000 terajoules G 92,410 terajoules H 121,410 terajoules J 133,410 terajoules 52 Add these together: And subtract from the whole: 173,410 – 133,410 = = 133,410 Home Back to energy

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11. Which process best shows the conversion of solar energy to chemical energy? F Prevailing winds causing windmills to spin G Green plants making their own food H Uranium producing heat to make steam J Tides generating electricity 14 Plants use the sun more efficiently than anything known to mankind. Home Back to energy

12. Which of the following is an example of solar energy being converted into chemical energy? F Plants producing sugar during the day G Water evaporating and condensing in the water cycle H The sun unevenly heating Earth’s surface J Lava erupting from volcanoes for many days 12 Sugar is chemical energy. It has calories and joules. Home Back to energy

13. An inventor claims to have created an internal combustion engine that converts 100 kJ of chemical energy from diesel fuel to 140 kJ of mechanical energy. This claim violates the law of conservation of — F momentum G inertia H energy J mass 48 chemical energy = mechanical energy + heat Home Back to energy

14. Home Energy = 2 x 2 x 4.184 Back to energy

15. This experiment probably was set up to determine — A how much mechanical energy the battery produces B the pH of water during electrolysis C the pressure created by an electric current D how much energy is converted to heat 9 A thermometer Home Back to energy

16. Container P and Container Q each were filled with 0.5 liter of water. The water was heated to 90°C. The table shows the temperatures after both containers were allowed to cool for 3 minutes. Compared to Container Q, Container P is a better — A conductor B absorber C radiator D insulator Small change. Larger change. 43 Home Back to energy

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18. Why is the sum of the products’ energy in this reaction less than the sum of the reactants’ energy? A Energy is given off as heat. B The products absorb available energy. C Energy is trapped in the reactants. D The reactants’ energy is less than the melting point of glucose. 37 + = + ≠ Reactants = Products The energy not stored in the bonds of the carbon dioxide and water must have left in the form of heat. Home Back to energy

19. The illustrations show a conservation-of-mass experiment. The solution in the beaker lost mass because — F materials have less mass at high temperatures G the mass of the reactants and products was less than 100 g H sodium sulfate (Na 2 SO 4 ) is lighter than air J some of the water molecules turned into gas 30 Before Before(100 g) After After( less than 100 g) Some of the water evaporated because of the heat. REACTANTS →Products The sum of the reactants = the sum of the products. Home Back to energy

20. An inventor claims to have created an internal combustion engine that converts 100 kJ of chemical energy from diesel fuel to 140 kJ of mechanical energy. This claim violates the law of conservation of — F momentum G inertia H energy J mass 48 chemical energy = mechanical energy + heat Home Back to energy

21. Fuel cells powered by plankton from the seabed can be used to operate instruments that monitor ocean currents and water temperature. These fuel cells get their energy by converting — F chemical energy to electrical energy G electrical energy to mechanical energy H hydroelectric energy to geothermal energy J mechanical energy to chemical energy 16 Batteries and fuel cells change chemical energy into electrical energy. Home Back to energy

22. Heat convection occurs in gases and liquids. Heat convection does not occur in solids because solids are unable to — A absorb heat by vibrating B transfer heat by fluid motion C emit radiation by reflecting light D exchange heat by direct contact 43 Home Back to energy

23. The moon’s surface becomes hot during the long lunar day because the sun transfers heat to the moon. This heat transfer is accomplished almost entirely through the process of — F convection G refraction H conduction J radiation 8 The space between planets has no elements in it and is therefore called a “vacuum”. Only radiation can travel through a vacuum. Convection and conduction use atoms to transfer energy. Home Back to energy

24. In which container is the substance unable to transfer heat by convection? 42 Gases and liquid can convect. Home Back to energy

25. The primary way liquids and gases transmit heat is by the process of — F reflection G conduction H radiation J convection 2 Gases and liquid can convect. Home Back to energy

26. A man who was sleeping wakes up because he hears the smoke alarm go off in his house. Before opening the bedroom door, the man feels the door to see whether it is warm. He is assuming that heat would be transferred through the door by — A conduction B convection C radiation D compression 33 Rule: Conduction: solids Convection: liquids and gases Radiation: doesn’t need matter at all Compression: does not apply to this question. Home Back to energy

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28. Fuel cells powered by plankton from the seabed can be used to operate instruments that monitor ocean currents and water temperature. These fuel cells get their energy by converting — F chemical energy to electrical energy G electrical energy to mechanical energy H hydroelectric energy to geothermal energy J mechanical energy to chemical energy 16 Batteries and fuel cells change chemical energy into electrical energy. Home Back to energy

29. Battery-powered cars produce less air pollution than gasoline-powered cars. However, one environmental concern of using battery-powered cars is that batteries — A are heavier than gasoline engines B waste more energy than gasoline engines C contain toxic substances that are difficult to dispose of D produce direct current rather than alternating current 49 Home Back to energy

30. In West Texas and Southern California, high winds drive turbines that generate electricity. One advantage that wind energy has over energy generated from solar cells is that wind energy — A is plentiful everywhere B can be generated at night C produces cleaner energy D is free of environmental hazards 45 Home Back to energy