Energy Review Guide

Back to Energy

1. 0.543 meters = __________ cm. 0.543 meters = __________ mm.

2. What is the unit for work and energy? Joules Newtons Watts

3. At 0 Celsius, water can be in these states: solid liquid gas

4. What type of potential energy is stored in food? _________________________

5. How much work is done if a 5-kg cat climbs 5 meters up a tree? Write the equation, plug in the numbers, solve and circle your answer.

6. How many watts would be expended if the 5-Kg cat climbed 5 meters in 9 seconds? Write the equation, plug in the numbers, solve and circle your answer.

7.

A

Which requires more energy? Circle your answer.

A) Climbing straight up a mountain.

B

B) Climbing up the mountain gradually by looping around it a few times.

C) The work is the same.

8. What is the difference between heat and thermal energy?

9. Which color absorbs heat quickly? White Black

10. Friction does work. How? Explain.

11. Write a statement of the relationship between the variables shown on the graph.

12. Complete the photosynthesis equation by writing coefficients on the lines:

Energy + 6CO₂ + ____ H₂O à C₆H₁₂O₆ + ____ O₂

13. What are the products if something like wood, oil, or coal is burned?

14. A man on the radio claimed that driving slower would not save gasoline. He didn’t understand that kinetic energy = 1/2mv². But you do! Use the equation to prove that driving slower would save energy. Choose 2 different velocities and compare the kinetic energies.

15. Driving in the city wastes more gasoline than driving on the highway. Why is this?

Remember, Work = Force x Distance!

1. How can water be made to boil at temperatures less than 100 degrees Celsius? Decrease pressure.
2. How can water be made to boil at temperatures more than 100 degrees Celsius? Explain. There are 2 possible answers. Increase pressure. Add salt.

Celsius	Fahrenheit	Kelvin
Boiling water = 100	boiling water = 212	Boiling water = 373.15
freezing water = 0	freezing water = 32	Freezing water = 273.15

3. What state, or phase, is water at when it reads 273 Kelvin? solid liquid
4. How does adding salt to ice affect the kinetic energy of the ice? Lowers KE

5. It is possible to boil water in a paper cup without lighting the paper on fire. How does this work? Heat is conducted away before paper can light.
6. If you measure out 50 ml of H20, how many grams does it weigh? 50 g
7. Heat travels from... Hot to cold!
8. A person comments that the average kinetic energy of the room is low. How are the molecules moving? slowly
9. How does the room feel? cold
10. What does a thermometer measure? Temperature
11. What does a calorie measure? Heat
12. Which color absorbs heat quickly? Black?
13. What is heat? Energy that moves from warmer areas to cooler areas.
14. What does temperature measure? It measures the average kinetic energy of a substance.
15. Pretend that you are walking on the beach at night. What direction will the wind blow? Toward the water
16. At higher altitudes, it takes less time to get water to boil. However, water boils at lower temperatures.
17. Air near the floor... A) Is dense. B) Is less dense. C) is warmer
18. A glass of ice water is sitting on a table. What is the temperature of the water? 0 degrees Celsius.
19. What is the relationship between pressure and temperature? They are proportional
20. Evaporation takes away. heat

Sample questions: