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1 Study Island Copyright 2014 Edmentum - All rights reserved. Generation Date: 12/10/2014 Generated By: Cheryl Shelton Title: Grade 7 Blizzard Bag Science-Day 5 1. Ryan is testing two types of light bulbs to see how efficiently they use energy. One is a standard incandescent bulb, and one is a compact fluorescent bulb. Ryan turns both bulbs on and finds that, after an hour, the incandescent bulb is too hot to touch, while the compact fluorescent bulb is warm, but not hot. Incandescent Bulb Compact Fluorescent Bulb If the purpose of both bulbs is to transform electrical energy into light energy, what can Ryan infer from his findings? A. The incandescent bulb is producing more light than the fluorescent bulb. The incandescent bulb is transferring more energy to its surroundings as heat. The fluorescent bulb is transferring more energy to its surroundings as heat. The fluorescent bulb is producing more light than the incandescent bulb.

2 2. Erma built the simple motor shown below with a battery, a permanent magnet, a copper coil of wire, and an iron bar. When the motor is turned on, the iron bar and coil spin in a circle. The motor transforms energy into energy. A. electrical; mechanical mechanical; electrical thermal; electrical mechanical; chemical 3. What characteristic feature of a wave is indicated by the letter C on the diagram below? A. loudness amplitude frequency wavelength

3 4. A light bulb is turned on. It produces light and warms up. Which statement is true? A. All the electrical energy is transformed to light energy. All the electrical energy is transformed to light energy and heat energy. All the electrical energy is transformed to heat energy. Some of the electrical energy is transformed to light energy and some is destroyed. 5. The speed of sound through oxygen at 0 C is 316 meters per second. The speed of sound through solid copper is 5,010 meters per second. Which of the following could be the speed of sound through liquid mercury? A. 6,130 meters per second 52 meters per second 228 meters per second 1,450 meters per second 6. Britney has four different materials of different masses. She decides to test their electrical conductivity by connecting each in a closed electric circuit and then measuring the amount of current that passes through them. Her results are collected in the table below. Material Mass (g) Current (A) W X Y Z Which material is most likely a metal? A. Y X Z W

4 7. Lucas plugs a lamp into the wall. The light bulb in the lamp turns on. What kind of energy transformation is this? A. Electrical energy is transformed into light and heat energy. Light energy is transformed into electrical and mechanical energy. Electrical energy is transformed into mechanical and heat energy. Light energy is transformed into mechanical and heat energy. 8. Emma sings into a microphone. The sound is transferred from the microphone to a loudspeaker that is plugged into the wall. Her voice comes out of the loudspeaker and sounds much louder than before. In this system, sound energy is being transformed into energy and then back into energy. A. mechanical; sound electrical; mechanical electrical; sound heat; sound 9. Jimmy held the end of a metal bar over a fire while holding on to the opposite end. After a few minutes, the end he was holding began to get very hot. Which process is illustrated in this example? A. induction radiation conduction convection

5 10. Pat pours cold, liquid cream into a cup of hot coffee. Which of the following describes how the hot coffee and cold cream will interact? The cold cream will immediately reach the same temperature as the coffee and spread A. evenly though the cup. The cold cream will drop to the bottom of the cup. When it warms, some of it will rise back to the surface. The cold cream will drop to the bottom of the cup. It will remain there, unless it is stirred. The cold cream will remain at the surface. When it warms, some of it will fall to the bottom of the cup. 11. How are sound energy and light energy similar? A. They are both kinds of mechanical energy. They both need a medium to travel through. They are both carried from place to place by particles. They both have a wavelength and a frequency.

6 12. Ramsay is testing the thermal conductivity of four different materials (W, X, Y, and Z) at room temperature. He cuts each material to the same length and touches one end to a 100 C iron cylinder. After 30 seconds, he measures the temperature of the opposite end of each material. His results are shown below. Which material is most likely a metal? A. Z Y X W