Energy Review Guide Name: Date: Period:

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1 Name: Date: Period: You are to use this review guide in addition to the study cards you should have already created using the guide previously given to you. I can state and explain the Law of Conservation of Energy. 1. What is the Law of Conservation of Energy? 2. Give an example to demonstrate the Law of Conservation of Energy. I can differentiate between a closed and open system and their relationship with matter and energy. I can provide examples of open and closed systems. Students perform an experiment by mixing Diet Coke and Mentos. They mix 50 grams of Mentos with 100 grams of Diet Coke in a 50 gram plastic Diet Coke bottle. The bottle is left uncovered. The students record the mass and temperature of their mixture every 5 seconds. They continue these observations until 10 seconds after the mixture stops bubbling. Their data is shown in the table below. Time (seconds) Mass (grams) Temperature (degrees Celsius) The data in the table show the temperature of the Diet Coke and Mentos system. The temperature of the surrounding air was not measured. Assuming that the total amount of energy remains constant, what conclusion about energy transfer does the temperature data support? A. Thermal energy was lost from the surrounding air and the system. B. Thermal energy was gained by the system and the surrounding air. C. Thermal energy was transferred from the surrounding air to the system. D. Thermal energy was transferred from the system to the surrounding air.

2 Students perform an experiment by mixing Diet Coke and Mentos in a closed Diet Coke bottle. They mix 50 grams of Mentos with 100 grams of Diet Coke in a 50 gram Diet Coke bottle. The bottle is kept closed. The students record the mass and temperature of their mixture every 5 seconds. They continue these observations until 10 seconds after the mixture stops bubbling. How do you think their data table will differ from their first experiment? What do you think will happen to the closed bottle? Why? I can explain that systems are separated by physical or mental boundaries. I can describe energy transfer in a system including dissipated energy (thermal energy). I can explain why dissipated energy is difficult or impossible to recapture. 1. A closed system. 2. Why does it appear that energy has been lost or disappears in an open system? 3. Here is a list of systems that are open or closed. Explain why you chose to call the system open or closed. Also state whether the system has a mental or physical boundary, or in some cases both. a. Human body Open / Closed b. Earth s Atmosphere Open / Closed

3 Energy Review Guide c. Ecosystem Open / Closed d. Hydrosphere (ocean) Open / Closed e. Solar System Open / Closed I can conduct experiments to explore energy transformations and trace the flow of energy from one form to another. I can explain and demonstrate knowledge of the different forms of energy including mechanical, light, thermal, electrical, sound, nuclear, and chemical. I can connect energy transfer to the natural world using real data. **** DO PAGES IN YOUR PACKET FOR PRACTICE **** CONVEYOR + COAL + HEAT BOILING WATER TURNS INTO STEAM TO TURN THE TURBINE

4 I can define and apply work = force x distance. I can define and apply power = (force x distance) / time a. You must exert a force of 4.5 N on a book to slide it across a table. If you do 2.7 J of work in the process, how far have you moved the book? b. How much work is done on a small car if a 3150 N force is exerted to move it 75.5 m to the side of the road? c. A child pulls a sled up a snow-covered hill. The child does 405 J of work on the sled. If the child walks 15 m up the hill, how large of a force must the child exert? d. If a runner exerts 350 J of work to make 125 W of power, then how long did it take the runner to do the work? e. Another engine reaches its top speed from rest in 7.5 s. It is able to perform 250,000 J of wok in that time. How much power does this engine have in that time? I can describe vibrations as it travels through a medium. When you drop a penny in a water fountain, explain the vibrations of the water particles as the energy travels through them. How does a wave move? (Hint: Describe the direction and movement of particles.) I can differentiate between longitudinal and transverse waves. Draw and label the parts of a transverse wave. Describe the motion of the energy as it passes through the medium.

5 Draw and label the parts of a longitudinal wave. Describe the motion of the energy as it passes through the medium. I can describe the properties of waves including speed, wavelength, amplitude, and frequency. A. B. Compare the frequency of the waves in two diagrams above. Compare the wavelength of the waves in the two diagrams above. Compare the amplitude of the waves in the two diagrams above. When frequency increases, amplitude. When frequency increases, wavelength. Frequency measures the. One wave per second equals 1 Hertz. I can differentiate between waves that do require a medium and those that can travel through a vacuum (light, electromagnetic). Give an example of a medium that mechanical waves travel through. What types of waves do not need a medium to travel through? Give an example. I can explain and apply v=λ x f (speed = wavelength x frequency). a. A tuning fork has a frequency of 310 Hz. The wavelength of the sound produced by the tuning fork is 1.32 m. Calculate the velocity of the wave b. What is the velocity of a wave with a frequency of 760 Hz and a wavelength of.45 m?

6 c. What is the frequency of a pendulum that is moving at 30 m/s with a wavelength of.35 m? I can describe how a medium effects wavelength and wave speed. How does the state of matter affect a wave s length and/or speed? (solid, liquid, gas)