Science Review 2

Force and Changes in Motion (13.2)

100

5) Maria pushes with equal force on two objects. Object 1 has twice as much mass as Object 2. Which of the following statements is true? A. Both objects will remain still. B. Object 1 will accelerate faster than object 2. C. Object 2 will accelerate faster than object 1. D. Both objects will accelerate at the same rate.

What is C. Object 2 will accelerate faster than object 1.

200

1) David and Peter were moving a bookshelf across the carpet in their classroom. Even though they pushed as hard as they could, the bookshelf would only move a few inches at a time. Which of the following best explains what happened as they tried to push the bookshelf? A. The force of gravity opposed the motion of the bookshelf. B. The force of friction opposed the motion of the bookshelf. C. When they tried to push the bookshelf, air resistance acted against them. D. When they pushed the bookshelf, the bookshelf pushed back with an equal and opposite force.

What is B. The force of friction opposed the motion of the bookshelf.

300

4) Will and Tammy are moving a dresser. They are arguing about which direction to move it. Will is pushing the dresser with a force of 5 newtons towards Tammy. Tammy is pushing the dresser towards Will with a force of 10 newtons. What happens to the dresser? A. The dresser does not move. B. The dresser moves towards Will. C. The dresser moves towards Tammy. D. The dresser moves towards Tammy, then back towards Will.

What is B. The dresser moves towards Will.

400

2) Philip is playing tug of war with Nancy. They both understand that to win the game of tug of war, one player must pull the flag over their opponent's line, but during this particular game, the flag tied to the center of the rope is not moving. What is happening to the rope in this example? A. Philip is applying more force in one direction. B. Nancy is applying more force in one direction. C. Philip and Nancy are applying equal forces in the same direction. D. Philip and Nancy are applying equal forces in opposite directions.

What is D. Philip and Nancy are applying equal forces in opposite directions.

500

3) While on a camping trip, Shane and Katie are traveling in a boat on a river. On their trip, the river's current carries them down the river at a speed of 5 meters per second (m/s). They don't need to row because the current is carrying them in the direction they need to go. If no other forces are acting on the boat, which of these statements describes the motion of the boat as it travels downstream? A. It speeds up. B. It slows down. C. It stays the same. D. It changes direction.

What is C. It stays the same.

Forms of Energy (10.2)

100

1) While playing at the park, Erica and her sister take turns going down the slide and playing on the swings. Which of the following is an example of change that is caused by applying energy? A. Erica continues to swing back and forth without trying. B. When Erica pushes her sister, her sister slides down the slide. C. Erica sits at the top of the slide and waits for her sister to finish her turn. D. When Erica stops pushing her sister on the swings, the swing eventually comes to a stop.

What is B. When Erica pushes her sister, her sister slides down the slide.

200

5) Todd can throw a baseball from the outfield all the way back to home plate. Why does he have to move his arm in order to make the ball fly all that way? A. He has to get the ball high enough in the air so the air can support it. B. The ball's energy can only be released if he lets it go above the ground. C. Moving his arm makes the ball's own energy take it in the right direction. D. He has to transfer some of his muscle's energy to the ball to make it move.

What is D. He has to transfer some of his muscle's energy to the ball to make it move.

300

3) When people want to use water to create electricity they generally build a dam to hold the water back, creating a large lake behind the dam. Why is it necessary to hold the water back with a dam in order to produce electricity? A. It increases the amount of water available. B. It increases the force with which the water flows. C. It forces the water to flow in the desired direction. D. It makes the water still enough to create electricity.

What is B. It increases the force with which the water flows.

400

2) Alex threw a stick in a river and watched as the river carried it away. He scooped a pail of water from the river and noticed that a leaf was floating in the pail without moving on the surface of the water. Why did the stick move in the river and the leaf stay still in the pail if it was all the same water? A. The river water cooled off and lost energy when Alex scooped it up into the pail. B. There is more water in the river than in the pail so the river could move the stick. C. The water in the river has enough energy to move the stick since it is flowing downhill. D. Wind could push the stick on the river but could not get to the leaf protected in the pail.

What is C. The water in the river has enough energy to move the stick since it is flowing downhill.

500

4) If Maria wants to have the best chance of blowing out all of the birthday candles on her birthday cake, she should bend down close to the candles, take a deep breath, make a small opening with her lips and then push her breath out. Why does doing it this way work the best? A. It keeps the air she breathed in cool enough to put out the candle flames. B. It makes the air come out with enough force to blow out the candle flames. C. The air forms a blanket over the candles and pushes the candle flames down. D. The air spins around when it comes out and hits all the candle flames this way.

What is B. It makes the air come out with enough force to blow out the candle flames.

Forms of Energy (10.4)

100

1) Heat flows in which direction? A. from solid objects to liquids B. from larger objects to smaller objects C. from warmer objects to cooler objects D. from more dense objects to less dense objects

What is C. from warmer objects to cooler objects

200

2) Which of the following materials would be a poor conductor of electricity? A. aluminum B. copper C. rubber D. steel

What is C. rubber

300

3) Fireworks convert chemical energy into which of the following kinds of energy? A. solar energy and sound energy B. thermal energy and light energy C. electrical energy and light energy D. nuclear energy and kinetic energy

What is B. thermal energy and light energy

400

5) Which of the following lists the forms of energy that electricity can be transformed into? A. heat, kinetic, light, and sound energy B. chemical, heat, light, and solar energy C. heat, kinetic, nuclear, and sound energy D. gravitational, kinetic, solar, and sound energy

What is A. heat, kinetic, light, and sound energy

500

4) Megan wants to determine if an electrical circuit has electricity flowing through it. Which of the following evidence is proof that the circuit has an electrical current? A. The circuit is a closed loop. B. A light bulb is lit in the circuit. C. The circuit's switch is in the closed position. D. Wires in the circuit are made of conducting material.

What is B. A light bulb is lit in the circuit.

Properties of Matter (8.3)

100

5) Which of the following solids will not dissolve in boiling water? A. baking soda B. sand C. sugar D. table salt

What is B. sand

200

3) Imagine you have a bucket of saltwater. Which of the following would be the best way to remove the water so that you're left with only salt? A. Stir the saltwater for a long time. The salt will form a crystal. B. Leave the saltwater to sit for a long time. The salt will settle to the bottom. C. Boil the saltwater. The water will evaporate and only the salt will remain. D. Freeze the saltwater. The water will sink to the bottom and the salt will rise to the top.

What is C. Boil the saltwater. The water will evaporate and only the salt will remain.

300

1) George's science teacher has a mixture of table salt and iron filings. Which of the following would be the best way to separate the salt and the iron filings? A. use a magnet to pull the iron filings from the salt B. add food coloring to the mixture to make the salt change color C. pour them into a beaker of water and see if the iron filings float D. heat up the mixture to see if the salt or the iron filings will burn away

What is A. use a magnet to pull the iron filings from the salt

400

2) Carrie has a container that contains thousands of mixed glass beads and iron beads of different shapes and sizes. Which of the following is the best way to separate them? A. The glass beads will float, so she could add water to the container and the glass will float to the top. B. The iron beads are magnetic, so she could separate the glass from the iron with a strong magnet. C. The iron beads might be heavier, so she could shake the container until the iron beads settle to the bottom. D. The iron beads are smaller, so she could pour the beads through a strainer and the glass beads will separate.

What is B. The iron beads are magnetic, so she could separate the glass from the iron with a strong magnet.

500

4) Abdul uses sugar cubes to sweeten his tea. He wonders whether stirring his tea will make the sugar cube dissolve faster or slower. If Abdul stirs his tea, what effect does it have on the rate at which the sugar cube dissolves? A. The rate that the sugar cube dissolves will speed up. B. The rate that the sugar cube dissolves will slow down. C. The rate that the sugar cube dissolves will remain the same. D. The rate that the sugar cube dissolves will slow down and then stop.

What is A. The rate that the sugar cube dissolves will speed up.

The Practice of Science (1.1)

100

2) Sonya wanted to know if mowing affects the health of grass during a drought. To find out, she collected data on how often her neighbors mowed their grass. Based on the information she collected, what is the BEST next step? A. Report her findings to her neighbors. B. Develop a plan to save everyone's lawns. C. Stop her neighbors from mowing their lawns. D. Find out if other things might be affecting the grass.

What is D. Find out if other things might be affecting the grass.

200

4) Brianna's class wants to determine if boys or girls recycled more paper each day. They set up separate recycling bins in the classroom and labeled them "Boys" and "Girls." The students then placed their paper items in the right bins. Which of the following should the students do each day before emptying the bins? A. Make lists of the different types of paper in each bin. B. Count and record the number of paper items recycled in each bin. C. Make a list of which student recycled which paper item in each of the bins. D. Record their estimate of the number of times students placed items in each bin.

What is B. Count and record the number of paper items recycled in each bin.

300

5) Kevin wanted to find out which of his toy cars, the Corvette or the Mustang, would roll downhill faster. He made a ramp by putting several books under one end of a board so that the board was slanted. Which would be the best way for him to perform his experiment? A. Roll each car down the ramp separately five times and estimate which car looked faster. B. Roll both cars down the ramp together one time and see which one gets to the bottom first. C. Roll each car down the ramp separately one time, and time them with the second hand on his watch. D. Roll both cars down the ramp together five times and record which gets to the bottom first each time.

What is D. Roll both cars down the ramp together five times and record which gets to the bottom first each time.

400

1) Jane is investigating to find out if bean plants grow taller in ordinary topsoil or special potting soil over a three week period. She sets up her investigation with 10 bean plants of equal size in each type of soil. What should Jane do each day to make sure she gets valid results? A. Water only the plants in special potting soil. B. Calculate the average plant height for each soil type. C. Move the plants in ordinary topsoil to different locations. D. Estimate the height of each plant's stem and record the estimate.

What is B. Calculate the average plant height for each soil type.

500

3) Thomas and Julie wanted to find out which material would insulate their teacher's coffee cup and keep the coffee hot for the longest period of time. They first wrapped her cup with bubble wrap and recorded the temperature of the coffee once every 15 minutes for 2 hours. They repeated the investigation, this time using newspaper instead of bubble wrap, but they got the same results for both materials. What could they do to make sure their results are valid? A. Repeat their experiment. B. Use tea instead of coffee. C. Use a different thermometer. D. Conduct their investigation in a colder room.

What is A. Repeat their experiment.