All Things Beautiful: Physics/Physical Science

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High School Physical Science, Test 2

Physical Science, Test 2

1. A box weighing 50N is picked up from the ground and placed on a shelf. What additional information do you need to calculate how much work was done to move the object?

a) The mass of the box.

b) The distance it was moved.

c) The time it took to move the box.

d) The velocity at which it moved.

2. According to Newton's Law of Universal Gravitation, the force that is formed between two masses is __________ proportional to the product of their masses and ________________ proportional to the square of the distance between them.

a) inversely, directly

b) inversely, inversely

c) directly, inversely

d) directly, directly

3. Which answer best describes the properties of a solid?

a) not rigid, no fixed shape, no fixed volume

b) rigid, fixed shape, fixed volume

c) not rigid, no fixed shape, fixed volume

4. Which answer best describes the properties of a liquid?

a) not rigid, no fixed shape, no fixed volume

b) rigid, fixed shape, fixed volume

c) not rigid, no fixed shape, fixed volume

5. When ice melts, latent heat is __________ which __________ molecular kinetic energy and __________ hydrogen bonds.

a) released, decreases, makes

b) absorbed, increases, makes

c) released, increases, breaks

d) absorbed, increases, breaks

6. If you have a metal pot on the stove and the handle becomes too hot to touch, the thermal energy in that handle likely got there through __________.

a) conduction

b) convection

c) radiation

7. Which of the following cannot happen, according to the Law of Convection of Energy?

a) The transformation of energy.

b) The transfer of energy.

c) The destruction of energy.

8. What is the property of a system that enables it to work?

a) inertia

b) energy

c) momentum

d) gravity

9. What do we call a quantity that indicates how warm or how cold something is relative to the standard?

a) temperature

b) heat

c) thermal energy

d) thermodynamics

10. What is the measurement of the average kinetic energy of the molecules that make up a substance?

a) temperature

b) heat

c) thermal energy

d) thermodynamics

11. Short Answer A basketball is released at a point exactly halfway between the moon and the earth. Draw the moon, earth and basketball and indicate the forces on the ball, using vectors. Explain your drawing using Newton's Law of Universal Gravitation.

12. Label each of the following as an energy transfer or energy transformation.

a) An ice cube melting slowly at room temperature. ____________

b) Your car burning gas to power the engine and make the wheels turn. ____________

c) A diver leaping off a cliff and starting to fall to the water. ____________

13. Short Answer Explain what specific heat capacity is. Use an example from everyday life to show that different materials have different specific heat capacities.

14. Short Answer You're using spray paint to paint a fence. You decide to paint the front holding the can one meter from the fence, and to paint the back, you hold the can two meters from the fence. How will the thickness of the paint on the two sides of the fence compare? Be as specific as possible. What type of law enabled you to find the answer?

15. Short Answer A vase resting on a high school has a potential energy of 40 J. Your cat knocks the vase off the shelf, and it falls to the ground. How much potential energy does the vase have when it is halfway to the ground?

16. Paragraph Answer Your aunt is staying for the weekend and complains every morning that the tile floor in the bathroom is so much colder than the wood floor in the hallway. Explain why she is technically wrong, being sure to discuss the Second Law of Thermodynamics and include the terms thermal equilibrium and conduction in your answer.

17. Paragraph Answer If you need to stop an out of control car, and want to live to tell the tale, do you run into a brick wall or a haystack? Include at least one equation and the terms impulse and momentum in your answer.

18. Paragraph Answer As one of our demonstrations, we made a cloud in a bottle. Explain the physics behind the demonstration.

19. Paragraph Answer If you have two objects and you want to increase their gravitational attraction, what two properties could you alter, and how?

Answers:

1. b

2. c

3. b

4. c

5. d

6. a

7. c

8. b

9. a

10. a

11.

12. transfer, transformation, transformation

13.

14.

15. 20, halfway; 0, full way

16.

17.

18.

19.

Grading: 2 points for each multiple choice, 6 points for questions 11 and 12, 8 points for questions 13, 14 and 15, 12 points for questions 16 and 17, 14 points for question 18 and 6 points for question 19.

Source: The questions come from reading Conceptual Physics.

Ocean Currents; Marine Science Activities for Grades 5-12

What causes ocean currents? Learn how wind, temperature, salinity, and density set water into motion, and they make an in-depth investigation of the key physical science concept of density. This series of activities will cover these topics. For grades 5-12.

Ocean Currents, Part I: Surface Currents {Wind and Temperature}

Ocean Currents, Part II: Salinity Currents

Ocean Currents, Part III: Temperature Currents

Ocean Currents, Part IV: Polar vs. Tropical Water

Ocean Currents, Part V: Ice Cubes Demonstration

Ocean Currents, Part VI: Layering Liquids

Ocean Currents, Part VII: Explorers and Ocean Currents

Additional Activity: Current Events

Literature Connections:

Adrift: Seventy Six Days Lost at Sea, Steven Callahan, Grades: 7–12
Bounty Trilogy, Charles Nordoff and James Norman Hall, Grades: 7–12
By the Great Horn Spoon!, Sid Fleischman, Grades: 4–8
Call It Courage, Armstrong Sperry, Grades: 3–6
The Cay, Theodore Taylor, Grades: 6–8
Darwin and the Voyage of the Beagle, Felicia Law, Grades: 4–8
Endurance: Shackleton's Incredible Voyage, Alfred Lansing, Grades: 7–12
Island of the Blue Dolphins, Scott O’Dell, Grades: 5–12
The Magic School Bus On the Ocean Floor, Joanna Cole, Grades: 1–4 (For younger grades, but still has some good information.)
Moby Dick, Herman Melville, Grades: 7–12
The Robinson Crusoe, Daniel Defoe, Grades: 7–12
Treasure Island, Robert Louis Stevenson, Grades: 7–12
The True Confessions of Charlotte Doyle, Avi, Grades: 5–8
The Voyager’s Stone: The Adventures of a Message-Carrying Bottle Adrift on the Ocean Sea, Robert Kraske, Reading Level is Grades: 3–6, but the story is wonderful and illustrations very informative.
Windcatcher, Avi, Grades: 4–7
The Wreck of the Waleship Essex, a Narrative Account, Owen Chase, Grades: 7–12

Sources and Resources:

Ocean Currents, Catherine Halversen, Kevin Beals, Craig Strang, Lawrence Hall of Science

The Atmosphere, Physical Science Topic for Middle and High School

Introduction

Atmosphere exerts pressure on everything that is in it. You can easily demonstrate this by putting a thin layer of water in a small bowl. Take a glass and invert it over the bowl. You should have no more water than is necessary to cover the lip on the inverted glass. Now you can take the glass away and add a few drops of food coloring to the water, so you can more easily see the water. put a candle in the center of the water in the bowl. Light the candle. Invert the glass over the candle and into the water as before. As you already know, the candle will eventually go out, but this time observe what happens to the water level within the jar. Because the candle used up all the oxygen (so there are less molecules), the air in the glass could not exert as much pressure as it did before. There becomes more pressure on the water outside the glass than on the water inside the glass. As a result, the greater outside pressure begins pushing water up inside the glass. Eventually, however, the water level goes back down because the extra water added to the force from the air pressure, and at some point this weight makes up for the lost air pressure. This is really the principle that makes barometers work.

Previous Knowledge

Topic Questions for Research

What are the layers of the earth's atmosphere, and what makes each layer unique?
What are the layers within the homosphere and what are the differences between these layers?
What are the layers and unique characteristics of the heterosphere?
Discuss atmosphere, atmospheric pressure and the barometer.
What ate jet streams and where do they exist?
Discuss the difference in temperature and air pressure in the layers of atmosphere.

Sources and Resources

Earth's Atmosphere: Earth Science Interactive Notebook
Exploring Creation With Physical Science, Jay Wile

Middle School Physical Science: Roller Coaster Physics

In this series, your student will be commissioned to be a roller coaster designer and as part of his training, he will look at some roller coasters that do not work and his task will be to figure out why they do not work and design a solution to the coaster's problem, using what he has learned about physics. Each student will need a blank notebook to write in.

Middle School Physical Science: Roller Coaster Design Training: The Snake

Covers Potential and Kinetic Energy, Law of Conservation of Energy and reviews Newton's First Law of Motion.

Middle School Physical Science: Roller Coaster Design: The Racing Roller Coaster

Reviews Speed, Velocity and Acceleration, looks at how Mass Affects Velocity and Therefore Momentum.

Middle School Physical Science: Roller Coaster Design: The Wooden Wonder

Covers mechanical advantage and reviews drag.

Middle School Physical Science: Roller Coaster Design: Marble Coasters

Students take what they have learned and apply it to making their own model roller coasters. They must identify at what points in the roller coaster the following are demonstrated:

Inertia
Centripetal Force
Friction
Angular Momentum
Linear Momentum
Highest Kinetic Energy
Highest Potential Energy
Negative Acceleration (Deceleration)

Other hands-on activities are suggested.

Middle School Physical Science: Roller Coasters: Marble Coasters

Now, its time to use all you have learned to make a model roller coaster.

You will be graded on:

Accurate labeling of terms
Successful verbal explanations
Smoothness and reliability of operation
Problem solving
Stability of the structure
Creativity
Teamwork

Materials

You can use either foam pool noodles and tape or cardboard paper towel, gift wrap and toilet paper tubes and tape. You will also need scissors and marbles, of course. You must have at least one curve and one loop and an energy source, such as gravity, that will send the marble all the way through the coaster. The marble must also land softly at the end and not fly out.
After you have built the coaster, test your coaster by sending the marble through it. Problem solve how to fix any problems your coaster has and make any necessary adjustments.

Identify

Label, either with written labels or verbally, with the following terms:

Inertia
Centripetal Force
Friction
Angular Momentum
Linear Momentum
Highest Kinetic Energy
Highest Potential Energy
Negative Acceleration (Deceleration)

Other possible projects:

Try building a roller coaster out of easy to bend wire.
Write a detailed description of a roller coaster you imagined, creating your own virtual ride, by making the description as realistic as possible, obeying all the laws of physics you have learned.
Research and write a report about how either Galileo or Newton influenced the study of physics.
Research and write a report about how the moon's gravity brings about tidal changes using the physics concepts and terms you have learned.
Research and report about how Newton's Laws of Motion affects bicyclist safety.
Research and write a report about pendulums and Newton's Laws of Motion.

Middle School Physical Science: Roller Coaster Design: The Wooden Wonder

Which items reduce friction and which increase it?

For this demonstration, you will need a spring scale. Begin by putting a rubber-band around the length of a wooden block that is at least 3x5x1. Hook the spring scale onto the rubber-band at one end of the block.
Now, pull the wood block across a large Styrofoam tray.
Place marbles in a large jar lid and then put the lid in the Styrofoam tray. Pull the block across the marbles.
Tape a piece of coarse sandpaper, that is as wide as the block and as long as the Styrofoam tray, to the tray. Pull the block across the sandpaper.
Remove the sandpaper and spread oil in the tray. Pull the block through the oik, being careful not to get oil on the scale.

Which setup(s) required the least force to move the wood block? Which required the most?
Anything that reduced the force needed is described as a mechanical advantage.

Review Activity: Drag

Drag is a type of friction. Have your student either come up with examples of Higher Friction, Higher Drag, Lower Friction, Lower Drag or have him sort those examples you have typed up for him.

Invader, the wooden roller coaster at Busch Gardens, Williamsburg.

Fixing the Wooden Wonder

This time the roller coaster you need to fix is a wooden roller coaster called the Wooden Wonder. Many roller coaster fans love the wooden coasters even though they don't turn you upside-down and can't be as big as metal coasters. This is because every day the ride on a wooden roller coaster is different depending on the humidity or dryness and the heat or cold.
Last night some teens were caught in the amusement park after closing time. I am afraid that they did something to the Wooden Wonder, and you are shown the ride operate with empty cars. After climbing slowly to the top of the first hill, it plummets to the bottom of the hill, clocking in a speed of 85 mph on the computer sensor read-out. The approved maximum speed for this coaster is 68 mph. When the train returns, you notice that the wheels appear yo have melted a bit. You and the maintenance crew walk along the track and after climbing to the top of the first hill, you all spot something glistening on the downhill tracks. What do you think was found on the track, and why? How can you explain what is happening to the cars, using Newton's First Law of Motion? What can the teens do as their restitution to get the train working as it should?

Math Connections

Work equals force times distance. Have your student use this formula to make up and solve math problems.

Middle School Physical Science: Roller Coaster Design: The Racing Roller Coaster

Warm Up: Speed, Velocity and Acceleration

To review these concepts, students either need to come up with examples of speed, velocity and acceleration or sort some examples that you give them on slips of paper. Review any concepts as needed.

Math Problems: Speed

Speed is the distance travels divided by the time it took to travel. Have your students solve some speed problems, according to the level they are comfortable with.

Activity: How Does Mass Affect Velocity (and Therefore Momentum)?

You will need two balls of the same size up of different masses such as a solid rubber ball and a hollow plastic one, or two cars of the same size and different masses.

A board that is about 8 inches wide and four feet long

stopwatch or clock with second hand

smooth floor

Predict which ball will get to the end of the ramp faster, the one with more mass or the one with less.

Release one ball at the top of the track and have someone time how many seconds it takes for the ball to get to the end. Be sure to start timing upon release and stop timing when the ball hits a certain point at the end.

Repeat with the second ball, making sure that this ball is released at the exact same place as the first ball was released.

What force started each ball moving? What forces stopped each ball's inertia or tendency to keep moving once it started moving?

What is the action force when each ball hits the pillow? What is the reaction force? How does this relate to Newton's Laws of Physics?

Why did the fastest ball travel at a higher velocity (get to the end faster)?

How might the mass of a roller coaster car affect the ride?

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Fixing The Racing Roller Coaster

This time you are shown another metal skeleton which sprawls across an even larger area than the Snake. This coaster has two tracks which are designed to race each other. One side has cars made from aluminum. They were expected to be the faster cars, but in fact they barely make it to the finish line. The cars on the other side are of the exact same design, but they are made of a mixture of heavier metals.

The first hill is 198 feet high and the second his is 140 feet high. Each of the rest of the hills is lower than the hill before it. The coaster starts at the first hill and goes to last him and then returns to the beginning.

Can you determine the reason that the cars on the one side move slower even though they are lighter? How might you redesign the slower cars to make them travel at a higher velocity?

Other related demonstrations:

Middle School Physical Science: Roller Coaster Design Training: The Snake

You have been commissioned to be a roller coaster designer and as part of your training you will look at some roller coasters that do not work and your task is to figure out why they do not work and design a solution to the coaster's problem, using what you have learned about physics.

Warm Up: Potential and Kinetic Energy

Practice telling the difference between potential energy and kinetic energy. You can have your students come up with examples, or you can write some down on slips of paper and have them sort them into the correct categories. Have them include this in their notebooks along with their own definitions of potential and kinetic energy.

Demonstration 1: Potential and Kinetic Energy Toy

James made this little spool toy that demonstrates potential vs. kinetic energy.

To make this toy, you will need:

a thread spool

a small rubber band

a toothpick

a dowel or the like

tape

a washer

Feed a rubber-band through the center of a wooden spool. Stick a toothpick through the loop the rubber-band makes at the end of the spool.

Tape down the loop of the rubber-band that sticks out of the end of the spool.

Break off the ends of the toothpick so that the spool can roll freely.

On the other end of the spool, place the loop through a washer.

Put a dowel on top of the washer, feeding it through the rubber-band loop.

Now turn the pencil around and around, tightening the rubber-band.

When the rubber-band is very tight, put your device on the floor and let go.

Or, you can hold the spool and watch the dowel act as a helicopter blade.

When did the potential energy enter the toy? When did the potential energy transfer into kinetic energy?

Demonstration 2: The Balls

You will need a hard floor that is clear of anything that could be broken by a bouncing ball.

Drop a basketball and then a tennis ball on the floor, noticing how high they bounce.

Now, holding the basketball in front of you, take the tennis ball and put it on top of the basketball so they are touching. Now drop the balls together on the floor, making sure that the tennis ball is still touching the basketball when the basketball hits the floor. If you were able to do this properly, the basketball should not have bounced as high as it did when you let go of the ball by itself. This was because most of the basketball's energy was transferred to the tennis ball. This shows the principle that things with more mass have more energy, at a given speed. This is why the tennis ball had so much more energy than when it was dropped by itself.

At what point is potential energy illustrated in this demonstration? At what point is kinetic energy illustrated?

Demonstration 3: The Energy Can

Before you begin problem solving, let's review some scientific facts that might help you. You will need:

an empty coffee can (1-lb. and 5'' diameter w/plastic lid)

Fishing sinker (1 oz.)

Hammer

1-2 Long Rubber-bands (6'')

2 paper-clips

nail

With a hammer and nail, punch one hole through the bottom of the can and one in the center of the plastic lid.

Thread the paper-clip onto one end of the rubber-band. Then thread the other end of the rubber-band through the hole in the bottom of your can. The clip should be on the outside of the can.

Slide the sinker onto the middle of the rubber-band.

Thread the free end of the rubber-band through the hole in the lid.

Attach the paper-clip to the rubber-band on the plastic lid so the band won't slip into the can.

Place the plastic lid tightly onto the end of the can.
Now you can explore potential and kinetic energy with this toy. Keep in mind the mathematical formula:

Potential Energy + Kinetic Energy = Total Energy

Can you predict where the potential energy is going to be the highest? Where is the kinetic energy going to be the highest?

Once you have made your predictions, push the Energy Can slowly across a smooth floor, and watch it travel until it stops by itself. Now, push it rapidly across the floor and watch it until it stops.

What did the Energy Can do when pushed slowly?

What did the Energy Can do when pushed rapidly?

How is the behavior of the Energy Can different from an ordinary can?

What conclusions can you make?

Why do you think the Energy Can acts differently from an ordinary can?

Where was potential energy the highest? Why?

Where was the kinetic energy the highest? Why?

Where is the potential energy the highest on a roller coaster?

Where is the kinetic energy the highest on a roller coaster?

As the Energy Can travels, some of its kinetic energy is changed to thermal (heat) energy in the form of friction. The thermal energy is waster kinetic energy. It does not help the Energy Can move so the can slows down. The potential energy was highest at the point where the Energy Can stopped moving away from you after the first push because that is where the most energy was stored inside it. Later trips lose more and more kinetic energy to friction, so it cannot build up as much potential energy.

The same thing happens with a roller coaster. As the coaster train is towed by electrical energy to the top of the first hill, the train gathers potential energy. The top of the first hill is where the train has the most potential energy. As the train travels to the bottom of the first hill, this potential energy is converted to kinetic energy. The bottom of the first hill is where the kinetic energy is the highest. The total potential and kinetic energy can never be more that what the electrical energy gave the train. In addition, friction converts some of the kinetic energy into thermal energy instead of movement, wasting some of the kinetic energy.

The Law of Conservation of Energy states that energy cannot be created or destroyed, only changed in form. How does this apply to the Energy Can or roller coasters? As we learned in Newton's First Law of Motion, the roller coaster cars will continue to move until another force, in this case friction (wheels on the track and the coaster's brakes), acts upon them.

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Fixing the Snake

The first roller coaster you are to work with is called the Snake because of all its hills and valleys look like a snake. The first hill is 160 feet tall, giving a thrilling first drop. Riders hurtle through the first tunnel at 61 mph. The designed decided to make the second hill even taller because coaster enthusiasts really love a terrific second drop. It is 200 feet high. The problem is that the cars won't go over the second hill. They make it part way and slide back and forth, finally stopping in the tunnel between the first and second hills. Can you discover anything that will help get this coaster up and running again? Write your solution in your notebook. Include in your explanation the facts you have learned (or reviewed) in this lesson.

Summer Bucket List: Zoom Ball

June 15, 2011

Zoom Ball is a fun summer toy you can make out of recycled materials (and you might throw in a little science while you are at it!)

You will need:

Two plastic soda bottles (preferably 1-liter, but all we had on hand was 2-liter, so that is what we used)

Two 12-foot lengths of string (we used much less, more like 6 feet)

Two plastic-ring, six-pack holders

Scissors

Masking tape

Cut the bottom off of two soda bottles.

Tape the ends of two bottles together to form a football shape.

Pull two strings through the bottle so that they come through both necks.

Cut a six-pack holder rings apart to form four, two-loop handles. (We needed to vary how long our ropes were depending on how large an arm span the kids had, so we didn't really use these and they aren't really needed.)

Partners hold the two handles on each end of the string. When the "ball" gets to you, you open your arms wide and the "ball" zooms away from you. As soon as it goes, you put your hands back together again so that your partner can send it back to you.

Red, White and Blue Punch (a lesson in Density)

Here is a fun way to make a patriotic punch and have a little lesson in density. You will need 3 different kid-friendly juices/drinks in red, white, and blue as long as the three colors of drinks are of different sugar content per serving. The larger the sugar content difference, the better your drink will layer. That’s because this involves a little kitchen science density. For your bottom layer you want something with close to 40 grams of sugar per serving, the middle layer should have around 20 grams of sugar per serving and the top layer should have as little as possible.

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The sugar content can be found on the package with the rest of the nutritional information. You can see that our white layer mixed just a bit with the other colors. This is because the sugar density did not differ enough in the layers. There are also a few more tips and tricks to get the layered effect.

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First start by filling your container, whether it be a large dispenser like in the above photo or individual glasses with the drink of the highest sugar content per serving, in our case, red Gatorade Fruit punch, which has 56 grams of sugar.

Next fill the container totally with ice. Place a large metal spoon across the top of the container so that the spoon is up against the side of the container. Now, slowly pour the drink with the next highest sugar content over the spoon and down the side of the container to fill it up one third of the way with the second color, in our case a white drink, Gatorade Frost: Glacier Cherry, which has 21 grams of sugar per serving. Try not to let any of it pour directly over the ice in the center or it will mix with the next layer and the colors will combine.

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Slowly pour your drink with the next highest sugar content very slowly over the ice to make your second layer. The ice will act as sort of a buffer.

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Lastly slowly pour the drink that has the least sugar content on top to form your top layer. We used Powerade Zero Mixed Berry, which has less than one gram of sugar. It is a light blue, however, and that may have contributed to it not showing up as a distinct layer.

If you would like to complete the lesson in density, you could try it again, using drinks that are a similar density and show how they mix instead of staying as layers. You could use Hawaiian Punch Fruit Juicy Red, which has a sugar content of 14 grams of sugar, instead of the Gatorade Fruit Punch and compare the results, as it has a density level much closer to the Gatorade Frost: Glacier Cherry, (21 grams of sugar per serving.) Have fun, drink up and learn science!

How to Make a Potential and Kinetic Energy Toy