Physical Science Study Guide | 8th
Rachel notices that many objects have rusted. Rusting is a chemical change that some metal and steel objects undergo when they are exposed to oxygen. Which option best describes a chemical change?
A change in matter that produces one or more new substances
What property of the water makes it possible for the needle to lie on the surface of the water?
surface tension
How do scientists describe energy?
the ability to do work
Place the color with the highest frequency wave at the top, and the color with the lowest frequency wave at the bottom.
1. violet 2. blue 3. green 4. yellow 5. orange 6. red
Maria's class has learned how to drop an egg without breaking it. After 0.2 s, the kinetic energy of the falling egg is 0.5 J. If its mechanical energy is 2.3 J, what is its potential energy?
1.8 J
Use the table below to calculate how much a dog weighs on the moon.
25 lbs
Have you ever noticed that some paints, glues, and nail polish remover have a peculiar smell? What you smell might be acetone. Acetone is a liquid at room temperature. Examine the graph showing what happens when liquid acetone becomes a gas. How many minutes did it take for all of the liquid acetone to become a gas?
30
According to the graph, what is the mechanical energy of the ball?
5 J
In 1973, the horse Secretariat set a record that still stands. This 500-kg horse ran the 2000-m track in 120 s. What was Secretariat's average kinetic energy? (1kJ = 1000 J)
69 kJ
While Robert was helping his father in the garden, he pushed a shovel into the ground to dig a hole in the dirt. He picked up a shrub, carried it to the hole, and held it to the whole, and held it while he lowered it into the hole. During which parts of this process does Robert *NOT* do work? Choose the *TWO* statements that apply.
He carried it to the hole. ; He held it while he lowered it into the hole
She activates it (hand warmer) and tucks it into the glove she is wearing. She holds her hands together, and before long, her hands are warm. Which best describes how her hands were warmed?
Heat was transferred by conduction, resulting in an increase in KE
How would her mass be affected by the different gravities on each of the planetary bodies? (Chiara and planets #23 graph)
Her mass would NOT change any where on any of the planetary bodies.
Based on this information (Chiara and planets #23 graph), what is her weight on Earth?
Her weight on Earth would be 100 lbs.
What can Eric conclude about what happens when heat is added or removed from an object after her completed his test with the ice cube?
His hand's energy decreases. His hand's heat is transferred to the ice to melt it. The temp of the cube stays constant until it's melted into water. During melting, energy is absorbed by the cube from his hand.
Leonardo da Vinci had an interesting way of writing in his journal. He wrote in Italian, but with his letters flipped horizontally and his words running from right to left. If you were to pick up his journal, what would make it easier to read?
Holding it up to a plain mirror
As the boys sat on the ice, the thermal energy of the ice *(decreased/increased/stayed the same/decreased, then increased)*, and some of the ice *(condensed/froze/melted/sublimed)*. As it sat in the cold air, the thermal energy of the water on the glove *(decreased/increased/stayed the same/decreased, then increased)*, and the water on the glove *(condensed/froze/melted/sublimed)*.
Increased. ; Melted. ; decreased. ; froze.
You might recycle plastic, metal, paper, and glass to conserve natural resources. What does it mean to conserve energy?
It is not created or destroyed
The pistons in an engine show how gas behavior can be applied to everyday events. Vol, temp, and press of a gas are all involved in the working of pistons. Which *TWO* show how these factors are related in pistons according to Charles's law and Boyle's law?
When the temperature is raised. ; The Piston moves up, decreasing volume and increasing pressure.
Which classification *BEST* describes the jam?
liquid with high viscosity
Michael loves to play the piano. When he hits a key, energy from the key starts a *(transformation/transfer/conservation/creation)* of energy to *(a string in the piano/his fingers/your eardrum/the air)*, to *(his fingers/your eardrum/the air/a string in the piano)* to *(the air/a string in the piano/his fingers/your eardrum)*, so that you hear the music he plays.
transfer. ; a string in the piano. ; the air. ; your eardrum
When the sun warms Earth's surface, thermal energy is ____________ to land and water.
transferred
Ocean breezes move because energy is _________________.
transferred by convection
Heat is the amount of energy _______________ the pot due to temp differences. It results in a(n) _________________.
transferred to. ; decrease in particle motion.
When you lie down on the sand, you spread beach towel down so that the sand will not make you too hot by______________.
transferring heat by conduction
In photosynthesis, solar energy undergoes a ________________ when it changes from light energy to chemical energy.
transformation
Matter can be measured in many ways for specific purposes. Which measurement depends on the force of gravity and is not a reliable measurement?
weight
Describe *two* examples of how energy from electromagnetic waves is used in technologies to do work. Include at least one wave property that is important for each example.
x-rays have high freq. when they pass through the skin and bounce off bones. high freq, short wavelengths. ; gamma rays reduce tumors. highest freq, shortest wavelengths
Which process names what happens when light is transmitted from air to water during the formation of a rainbow?
refraction
Which of these materials could sound travel through? Choose the *THREE* that apply
Air, rock, and water
Which *TWO* types of potential energy do the springs have?
Elastic and gravitational
IDENTIFY *PURE* SUBSTANCES: (air/smog/oxygen/sugar/coffee/choco milk)
Oxygen and sugar
Which form of energy is produced when two objects are rubbed against each other?
Thermal
Energy from the sun warms the beach by ____________________.
Transferring heat by radiation
George is writing a newspaper article about the fire at the local library. His introductory paragraph has an example of conservation of mass. Choose the sentence that illustrates conservation of mass.
' All that remained of the books and magazines were ash, water vapor, and carbon dioxide fumes. '
IDENTIFY *MIXTURES*: (air/smog/oxygen/sugar/coffee/choco milk)
Air, smog, coffee and choco milk
Why do you fill a basketball, a football, a soccer ball, or a volleyball with a gas (air) instead of a liquid? Choose the *TWO* statements that apply.
A liquid would make the ball too heavy. ; Gases can be forced into a smaller volume than a liquid can.
A large volume of oxygen can be put into a small tank because oxygen is a gas, and gases can be ___________.
compressed
Which of the following scenarios describe an energy transformation? Choose the THREE scenarios that apply
A toaster being used to toast bread. ; a car horn honking. ; a lamp being turned on.
Choose the sentence that illustrates the conservation of mass
All that remained of the books and magazines were ash, water vapor, and carbon dioxide fumes
As they were heated, the plastic softened and were formed into new shapes. These plastics were *(amorphous/crystalline/vibrating/viscosity)* solids,
Amorphous
Half the vertical distance from the trough to the crest of a wave
Amplitude
What could Eric conclude about what happens when heat is added or removed from an object after he completed his test with the mug of hot chocolate?
Arrow A shows the direction heat flowed because the temp of his hand increased as heat was absorbed by his hand.
Describe the behavior of the acetone particles during each phase represented by the diagonal and horizontal portions of the graph.
As the liq. warms, particles start to slide against each other and separate from at 20 min. The acetone completes changing states at 30 min. The acetone is a gas at 35 min.
At what point on the track does the car have the greatest PE? the greatest KE?
At the highest point on the track. ; at the lowest point on the track.
Which of these statements describe visible light waves? Choose the *TWO* that apply
Blue light has a shorter distance between wave crests than orange light. ; Red light has a longer distance between wave crests than blue light.
These (amorphous) solids are different from *(amorphous/crystalline/vibrating/viscosity)* solids, which melt at a specific temp
crystalline
Chloe is training for her first half-marathon, which requires her to run 21.1 km. Before she runs, she carefully chooses the foods that will give her energy her body requires for the race. She stands still at the starting line, then she starts running, her body warming up as she runs. What *THREE* energy transformations take place in this?
Chemical energy to Kinetic energy Potential energy to Kinetic energy Chemical energy to thermal energy
What word described the type of energy transfer represented? [ Man holds a steel rod above lit up candle ]
Conduction
What word described the type of energy transfer represented? [ boiling water in a pot ]
Convection
Betty is sitting on of her surfboard out in the ocean. She is waiting for the perfect wave to come along so she can ride it in to shore. As she waits, she notices that the waves roll by in patterns, or sets. As the top of each wave passes by Betty, it pushes her up. Which part of the wave does this?
Crest
What is meant by the conservation of energy?
Energy cannot be created or destroyed
Min is conducting an experiment where he compares the properties of water and lemonade. The first stage of the experiment is focusing only on the physical properties of the water and lemonade. Which comparison point would Min *NOT* use in his first stage?
Flammability
The distance a wave travels before repeating
Frequency
Based on the model, what is the chemical formula of sulfuric acid? [ 2 Hydrogen - 4 Oxygen - 1 Sulfur ]
H₂SO₄
Compare what you know about the materials in the table. Which material would you choose? Explain your answer.
I would choose the material with the highest specific heat, Beryllium. With higher specific heat, it'd take longer to heat up when the spacecraft enters the atmosphere.
Which statement would the researchers find to be true? Choose *TWO* that apply.
It takes less energy to raise the temp. of a sample of stainless steel than it does for a sample of beryllium It takes more energy to raise the temp. of a sample of beryllium than it does for a sample of titanium
Which of these statements is true about the behavior of light?
Light behaves as a wave or a particle depending on the situation
When Corey observes the straw through the side of the glass, the straw appears to be broken into two parts. Which statement explains Corey's observation of the straw?
Light waves are bending when they travel from one material to another
The contents of the bucket were in a *(liquid/gas/solid)* state. If the contents were heated up enough, they would change to a *(liquid/gas/solid)* state.
Liquid. ; gas.
Which property would help to determine whether matter is a solid or a liquid?
Mass
Explain how gravity affects mass. (Chiara and planets #23 graph)
Mass is a constant value. No matter where you are, gravity doesn't affect your mass.
Which of these choices are forms of energy? Choose the THREE that apply.
Mechanical, chemical, and electrical
(Roller-coaster #29) Explain how energy is conserved in the roller-coaster ride.
No energy is created or destroyed. Energy is either transferred or transformed, never destroyed or created.
Monica was using different colored pieces of clear plastic for an art project. Her little brother came and scattered the plastic all over the photograph of the image she was using as a guide. As she was cleaning up, she noticed that the image appeared differently behind certain colors of plastic. Why was this?
Only the color matching the plastic can pass through, leaving everything else shades of black.
What word described the type of energy transfer represented? [ sun shining ]
Radiation
What info did she need to find the density of each liquid? (Graph of #15)
She needed the mass and vol of each liq.
How did she calculate density (of each liquid as shown in graph #15)?
She used Mass/Volume
The number of waves that pass a given point in a certain amount of time
Speed
Which of these terms is defined as the ability to cause motion or create change?
energy
They place meat and veggies from the fridge onto the hot grill. When the food is cooked and taken off the grill, it's at a much higher temp than it was before it was cooked. Which statements are true about the food? Choose the *TWO* that apply.
The KE of the food particles increased, causing the food temp to rise. ; The thermal energy of the food increased.
You are camping and it is time to build a campfire. You gather logs and stack them loosely, and then you add small twigs and leaves to make the fire easy to light. As you sit by the fire, the logs burns bright in the darkness, and you feel the heat coming toward you. Which of these statements are true about the amount of energy transformed in the camp fire? Choose the *TWO* that apply.
The amount of heat and light energy released equals the amount of chemical energy that is burned. ; The Law of Conservation of Energy applies to these transformations.
How do the melting point and the freezing point of gallium compare to each other?
The freezing point of gallium equals its melting point
Which liquid sinks to the very bottom, and which floats at the very top? Explain. (Shown in graph #15)
The honey sinks to the very bottom because it's the densest. The oil floats at the very top because it's the least dense
Which food item is homogeneous and which is heterogeneous? Explain.
The juice is homogeneous because it's chemically bonded and difficult/impossible to separate The chicken noodle soup is heterogeneous because it's *NOT* chemically bonded and easy to separate
Which statement best explains to difference in the behavior of the door when the weather is warm compared to when it is cool?
The metal in the door expands when it becomes warm due to an increase in kinetic energy, and contracts when it's cooler
A new home had a wooden floor put down in cool weather. As the weather became warmer, the floor started to buckle, rising up in the middle of the floor. The floor was fixed by trimming the edges of the floor so that there was a space between the flooring and the wall. Choose the response that best explains why this helped to make the floor flat again.
The particles in the floor increase in thermal energy in warm weather, increasing the kinetic energy of its particles and making it expand. Trimming it gave it room to expand.
Nakeem and his team were playing basketball in the gym, and all the basketballs were firm and bounced well. When the team went outside, the same basketballs seemed a bit flat and would not bounce well. Which statement provides the best explanation for what happened to the basketballs?
The temp. outside was colder than the temp. in the gym, so the pressure of the air in the balls decreased
The planet Venus is surrounded by a thick layer of gases. In fact, the atmosphere pressure on Venus is over 90 times greater than the atmosphere pressure on Earth. Which statements are true about boiling water on Venus? Choose the *TWO* statements that apply.
The temperature of the water will remain constant while it boils. ; Water will boil at a higher temperature on Venus than on Earth.
Which statements correctly describe how heat flows? Choose the *TWO* statements that apply.
The warmth from the burner is flowing to the cold water and increasing its temp. The warmth from the water is flowing to the ice and melting it.
Betty is sitting on of her surfboard out in the ocean. She is waiting for the perfect wave to come along so she can ride it in to shore. As she waits, she notices that the waves roll by in patterns, or sets. Betty sees a large speed boat pass in the distance. The boat's motion causes small waves to form and travel outward. What will most likely happen as the larger ocean waves approach the waves created by the boat?
The waves will momentarily create a new wave with a crest higher than the original waves.
When you cook dinner, you *HEAT* your dinner on a hot stove. When you place a piece of a cool metal in the sun, it is *HEATED* by the sun's energy. Why is heat the correct term to use in these examples?
They show that heat flows from something warmer to something cooler
What happens to a liq when you keep on cooling it until it changes?
it becomes a solid
(Roller-coaster #29) Include descriptions of at least one energy transfer and at least *TWO* energy transformations.
Transfer: KE is transferred to the tracks, causing it to shake. Transformed: KE to PE, PE to KE, and KE to Thermal Energy
The distance a wave travels in a certain amount of time
Wavelength
Describe how light and sound waves are affected when they move from air to water.
When light waves move from air to water, the speed is accelerated. When sound waves move from air to water, the speed is increased more than three more than the light's speed. Light and sound travel quicker in water because molecules are closer together in water than air.
A student gets ready to go to school one day, and he finds out that his car's battery is dead. The headlights will not come one, and the car won't start. What transformations usually happen when the battery is active and the headlights come on?
chemical ➞ electrical ➞ light
Sunlight enables plants to use water and carbon dioxide during photosynthesis to make and store sugar. Any animal that eats the plants can convert the sugar into the energy it needs to move from place to place. Which *THREE* types of energy involved in this example?
chemical, kinetic, and electromagnetic
These plastics were amorphous solids, and their particles are arranged *(far apart/in no regular pattern/in regular, repeating patterns/so that the particles slide by each other)*
in no regular pattern
Ruth's birthday celebration included several party balloons that were filled with helium. As afternoon sunlight filled the room over time, the room became warmer, the room became warmer. As the temperature in the room increased, the volume of the gas in the balloons *(changed randomly/decreased/increased/stayed the same)*, because gas temperature and volume are *(not related/directly proportional/indirectly proportional/opposites)*
increased. ; directly proportional.
Two boys are holding onto the end of a long piece of string, and they move it up and down to make a wave. They begin to move the string faster and faster. When they move the string, the energy *(remains the same/increases/decreases)* and the frequency *(decreases/increases/remains the same)*
increases. ; increases.
The louder the singer can go, the more *(volume/intensity/pitch/density)* the vibrations have, and the better chance of shattering the glass.
intensity
Water, air, building, food, and everything visible and invisible has mass and takes up space. What is the word used to describe anything that has mass and takes up space?
matter
A pure substance is a single kind of matter. A(n) _________________ is made up of *two* or more substances that are together in the same place, but each substance keeps its own properties.
mixture
The areas on the wave where the amplitude is zero are called *(compressions/nodes/rarefactions/antinodes)*, and the areas on the wave where the amplitude is the greatest are known as *(rarefactions/compressions/antinodes/nodes)*.
nodes. ; antinodes.
Suppose it is a hot summer day, and a solid ice cube melts, forming liquid water. What kind of change is involved?
physical
The vocalist must match the *(pitch/volume/intensity/density)* of their voice to the natural *(mass/thickness/loudness/frequency)* of the glass.
pitch. ; frequency
Which of the following describes the kind of energy that comes from the sun?
radiant energy
Energy travels to Earth as electromagnetic waves from the sun. When these waves reach Earth, some waves bounce off of the atmosphere back into outer space. Which word describes the phenomenon?
reflected
Lauren wants to add in the additional layers shown in the table below. Assuming all layers with have a volume of 3 mL, which of all the substances with float on top? (graph #67)
rubbing alcohol
The gravitational potential energy (GPE) of the bird feeder is the result of *(its elasticity/the gravitational pull of earth/ its kinetic energy/ its speed and mass)*. The GPE of this full bird feeder is *(22Nm/ 40 Nm/ 18 Nm/ 10 Nm)*.
the gravitational pull of earth. ; 40 N*m
