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Standards: 7.4A(xli) 7.4A(lv) 7.7C(i) 7.7C(ii)

TOPIC Texas Science - TEKS Force, Motion, and Energy GRADE 7th STANDARDS 7.7C

Essentials Engage Explore Explain Elaborate Evaluate Intervention Acceleration All

Explore Teacher Guide

test : Preview ElementaryScopes Standards Student Management Assessments

7.7C Forces in Everyday Life

STEMcoach ↗

It looks like your students will be comparing the turgor pressures of potato slices in water and salt solutions.

This investigation provides a great platform for students to extend their understanding. To learn more about sustained inquiry, visit this

STEMcoach section.

Description

In Part I of this Explore activity, students compare the turgor pressures of potato slices in water

and two salt solutions through an investigation.

In Part II of this Explore activity, students plant seeds in wet plaster of Paris to demonstrate and

illustrate how forces affect motion in everyday life, such as the emergence of seedlings.

Materials List

Printed Materials:

Teacher Printout: none

Student Reference Sheet: none

2 Student Guide per group

1 Student Journal per student

Reusable

3 250mL beakers per group

1 Forceps per group

1 Digital camera per group

1 Computer per group

1 Timing device/stopwatch per group

1 Metric ruler per group

1 Permanent marker per group

1 9 oz plastic cup per group

Contents

Description

Materials List

Preparation

Background

Part I: Turgor Pressure

Part II: Emergence of

Seedlings

Reflections and Conclusions

View As Student Feedback Speech a A

1 Heavy duty, plastic knife per group

1 Sharp knife per teacher

Consumable

2 Beans of any kind per group

1 Craft stick per group

1 Sliced potato 5 mm thick per group

1 Paper towel per group

480 g of salt per class

3 oz plastic cup per group

30 g of Plaster of Paris per group

200mL of water per group

3 L of water per class

15mL of water per group

Preparation

Print one Student Guide for each group in your class. Print one Student Journal for each group in your class.

Part I: A single 10-pound bag of potatoes is enough for multiple groups and classes to use throughout the day. Slice the

potatoes to 5 mm thickness. Store covered in water prior to distributing one slice to each group in your class. When a group

receives a potato slice, they should cut it into 3 equal-sized potato sticks. (The potato sticks resemble french fries.)

Prepare a 4% Salt Solution by adding 40 g of salt to 1 L water. (40 g is 2 tbsp of salt.) Prepare quantities so that each group in

the class receives 200 mL of 4% Salt Solution. Prepare a 20% Salt Solution by adding 200 g of salt to 1 L water. (200 g is 2/3

cup of salt.) Prepare quantities so that each group in the class receives 200 mL of 20% Salt Solution. Be sure each group also

Collect and Analyze Data with a Metric Ruler

A metric ruler is used to collect data whenever it is used to measure the length of an object. In this activity, the metric ruler is used to

collect data on the original length of the potato sticks as well as the amount the potato bend after being removed from the different

solutions.

A metric ruler is used to analyze information when the metric ruler is the object being observed to gather information. In this activity,

students will analyze the amount the potato bends after being in different levels of salt solutions.

Make sure students understand how to use a metric ruler properly in the classroom laboratory and refer to the Process Skills Primer in the

Teacher Toolbox for more information on all Science Tools.

Collect and Analyze data with a Digital Camera

A digital camera is used to collect data when it is used to capture a visual image to record the object of study at a specific point in an

investigation.

A digital camera is used to analyze information when images are captured to compare objects of study under different conditions or as a

series of images that show possible change over time. In this activity, students will use the digital camera to help them analyze forces in

plants' turgor pressure and the emergence of seeds. The turgor pressure will be analyzed with the photographs of the potato during

different stages of the experiment. The digital camera will be used to document the germination of the seed planted in the plaster of Paris.

Make sure students understand how to use a digital camera properly in the classroom laboratory, and refer to the Process Skills Primer in

the Teacher Toolbox for more information on all Science Tools.

STEMcoach ↗

Your students will need to work in cooperative groups in order to complete this activity. Try giving them each a well-defined job during the

group task. This will encourage them to work together and will eliminate the problem of one student doing all of the work while the others sit

and watch. Also, see the Supporting Documents for more great ideas. In addition, check out the video related to this!

receives a beaker of 200 mL of water.

Label three beakers for each group as follows: Water, 4% Salt Solution and 20% Salt Solution. Plan to distribute the beakers

with 200 mL of the corresponding liquid to each group.

Part II: Pre-measure 30 grams of dry Plaster of Paris in small disposable cups for each group in your class. 30 grams is

approximately equal to 2 tablespoons. Students will add water to the mixture. Test this out prior to the activity. The mixture

should be thin and resemble liquid glue. The ratio is usually 2 parts plaster to 1 part water. Determine the amount of water

needed in mL and direct students to measure and add that amount in Part II of the activity. (Note: the materials list directs 15

mL per group.)

Background

STUDENT GUIDE

A force is a push or a pull that can change the motion of an object. Forces are everywhere. Forces, including gravity, are

constantly acting upon plants and cause them to be in motion. Plants can be in motion just like we are in motion. Plants move

when they grow or respond to their environment.

Turgor Pressure

Water within a plant cell exerts a force, called turgor pressure, which pushes outward on the cell wall. The ability a plant has to

maintain a strong upright position and return to the upright position when blown by the wind is the result of force from turgor

pressure. When plants do not have enough water in their cells or the water has been removed from the cells, the cells begin to

shrivel. They shrivel and collapse because of the reduced turgor force pushing outward on the cell wall. If enough cells collapse,

the plant wilts because the force of gravity is greater than the force from turgor pressure. Work is done when a force causes an

object to move a distance, such as when water in a plant cell forces a wilted plant to return to its upright position.

Emergence of Seedlings

Imagine yourself trapped under a bookshelf. To stand up, you must exert a force on the bookshelf greater than the force pushing

down from the bookshelf. Seedlings work the same way. Seedlings can only emerge from the soil when they push upward,

exerting a force on the soil greater than the downward force of gravity. The turgor pressure inside of the plant cells must be high

in order to have enough force to push up on the soil. If the turgor pressure is low, the seedling will not have enough force to

emerge and overcome the force of gravity.

STUDENT JOURNAL

High and Low Turgor Pressure graphics

1. Define force:

A force is a push or a pull that can change the motion of an object.

2. How does gravity affect objects?

Gravity is a force that pulls.

3. What forces act on or within plants?

Some of the forces that act on plants would include gravity and wind. Turgor pressure is a force within the plant.

4. What is turgor pressure?

Force due to water in the cell pushing outward on the cell wall, allowing plants to stand up straight.

5. What happens to a plant with low turgor pressure?

The decreased force from within the cell causes it to collapse and shrivel. When enough cells shrivel, the plant wilts.

6. What must a seedling do in order to emerge through the soil?

The force due to the seedling’s turgor pressure must be greater than the force of gravity.

Part I: Turgor Pressure

STUDENT GUIDE

Procedure:

1. Obtain a potato slice from your teacher. Cut the slice into three potato sticks that are equal in length, width, and height.

They will resemble French fries.

2. Before placing the potato sticks in the beakers, measure the length of the potato sticks (figure 1). Record the initial length

of all three potatoes in the 0 (Initial) row in Data Table 1: Potatoes in the Student Journal.

3. Place 1 potato stick in a beaker labeled: Water.

4. Place 1 potato stick in a beaker labeled: 4% Salt Solution.

5. Place 1 potato stick in a beaker labeled: 20% Salt Solution.

6. Start timing and wait 10 minutes. Use a pencil to divide a paper plate into thirds, and label one third - water, one third - 4%

salt solution, and one third - 20% salt solution. Set the plate aside. Complete question 2 in the Student Journal while

waiting.

7. At 10 minutes, use the forceps to take the potato sticks out of the water and salt solutions, and place them on the labeled

paper plate. Do not mix up your potato sticks as they will go back into the same beakers.

8. For each stick, hold the potato piece by the top edge. The bottom edge of the potato will be on the table so that it stands

lengthwise. Pull the top edge down toward the bottom edge as far as you can bend it without breaking the potato. Use

Measuring length of potato sticks

teamwork to measure the distance from the top edge to the bottom edge of the potatoes (as shown in figure 2), and

measure the distance that shows how it will bend without breaking.

9. Record your results for the 10 minutes in the 10 minutes row on Data Table 1: Potatoes in the Student Journal.

10. Return the sticks to the beakers. They go back into the same beaker that they came out of. Do not mix them up.

11. Start timing and wait another 10 minutes. While waiting, continue adding detail and labels to the diagrams of the initial set

up of each beaker for question #2 in the Student Journal.

12. After an additional 10 minutes, use the forceps to take the potato sticks out of the water and salt solutions and place them

back on the labeled paper plate. Measure the distance, like before, to determine how much the slice will bend without

breaking.

13. Record your results for the 20 minutes in the 20 minute row on Data Table 1: Potatoes in the Student Journal.

This should be enough time for the salt solutions to show results. However, depending upon the type and age of the

potatoes used, you may need to instruct your student to continue obtaining data for additional 10-minute time intervals.

14. Sketch the bend of each potato in the small box to the right of each set up in question 2 of the Student Journal.

15. Clean up as directed by your teacher.

16. Complete the remaining questions for Part I in the Student Journal.

STUDENT JOURNAL

Potato Slices and Turgor Pressure. Record your observations in the table below.

Data Table 1: Potatoes

Time (min) Measurement (mm) Distance Between the Top and Bottom of the Potato Stick.

Water 4% Salt 20% Salt

0 (Initial) Will be the length of the potato Will be the length of the potato Will be the length of the potato

10 varies varies varies

20 varies varies varies

Data will vary, however, students will see that the distance between the top and bottom of the potato slice will decrease as

time increases in both salt solutions. The results of the potato in the 20% solution will be the most dramatic.

2. Draw and label a diagram that show the parts of the initial set up of the potato sticks in each beaker in the large space to

the left in each of the boxes below.

Measuring potatoes

3. Sketch the “bend” of each potato stick in the right side of the boxes after your final measurement.

4. Which potato had the greatest amount of turgor pressure? Explain.

The potato in water had the greatest amount of turgor pressure because it was the most rigid.

5. Which potato had the least amount of turgor pressure? Explain.

The potato in 20% salt solution had the least amount of turgor pressure because it was more pliable.

6. Draw a picture of what you believe a potato cell would look like under a microscope after being in water and another picture

of what it would look like after being in a 20% salt solution.

Part II: Emergence of Seedlings

STUDENT GUIDE

Procedure:

1. Mix 2 tablespoons of Plaster of Paris with 1 tablespoon of water in a plastic cup.

2. Stir the mixture with a craft stick. More water may be needed to reach a consistency similar to thin, liquid glue.

3. Write your group members’ initials on the side of the cup.

4. Place 2 seeds in the mixture, and set aside per your teacher’s instructions.

5. Throw the craft stick in the trash, and clean up any mess that may have been made.

6. Observe your cups daily for any changes.

7. Keep the top of the dried plaster wet by slightly dampening a piece of paper towel. Fold the damp paper towel twice so that

you have a double layer, and set it on top of the dried plaster. Repeat as needed.

8. Record your observations in the Student Journal.

STUDENT JOURNAL

1. Describe what happened to the plaster when the seeds began to grow.

The seed pushed through the plaster, breaking it apart.

2. How does a seedling emerge through the soil?

The turgor pressure in the sprouting seed has to have enough force to be greater than the force of gravity as it pushes up.

3. Why is it important for the seeds to be watered? Explain in terms of force and turgor pressure.

The seeds soak up the water and their cells increase their turgor pressure. When the seeds have enough turgor pressure,

Diagram of potato slices in different solutions

water and 20% salt

they will break out of their seed coat and push up through the soil. They have to have more force pushing up than the

gravity that is pushing down on the seed.

4. If the 2 cm seedling was pushing upward with a net force of 12 N, how much work was done?

Work = Force x Distance.

12 N x 2 cm = 24 Joules of work

5. If a seed did not have enough force to push through the plaster and did not grow, how much work was done? Explain.

No work would be done because in order to have work, the object must move. If the seedling does not grow, no work was

done

Reflections and Conclusions

1. How does force affect the motion of plants?

There are many forces acting upon plants. When turgor pressure changes, it affects the motion of the plants. When turgor

pressure is high, it keeps the plant upright or pulls the plant upright after it has wilted or been blown in the wind. When

turgor pressure is low, gravity is a greater force and it pulls the plant down. When seedlings are pushing upward, it has to

have a great enough force to push up against gravity which allows it to grow (move) upward.

2. Why do grocery stores have water misters in the produce department? Explain.

They spray water on the plants to keep the turgor pressure high in the produce. Plants with higher turgor pressure are

crunchy. Wilted vegetables will not sell.

3. If flowers begin to wilt, is there anything that can be done to save them?

Plants are not necessarily dead when they are wilted. They have low turgor pressure and will need water. If plants can

increase their turgor pressure, they can recover.

4. Predict what would happen to a plant cell if their turgor pressure was too high.

The plant cells would get too big and burst.

5. Create a scenario that demonstrates a situation that also explains how a seedling emerges from the soil.

Answers will vary but may include being buried in the sand and pushing their way out, pushing a boulder uphill, etc

6. Compare the turgor pressure of a cell to a water balloon.

When the turgor pressure in a cell is high, it will be swollen and firm from the water inside. It is just like a water balloon. If

bent, plants with high turgor pressure will snap like fresh celery; when a water balloon is filled with water, it will break open

when bent or broken.

ELPS Strategy

Graphic Organizer

After the students have had time to explore the lesson, provide them with a sheet of construction paper. Have the students fold the paper

in half “hamburger style” and draw a line in the middle to create two sections labeled Example 1 of Forces in Everyday Life – “Insert

example here” and Example 2 of Forces in Everyday Life – “Insert example here.” Ask them to draw a diagram under each tab that best

represents the example, and use the provided sentence stems to explain their diagrams. Ask them to share their graphic organizer with

the class, and encourage them to read their sentences out loud.

© 2014 by Rice University. All rights reserved. While every attempt is made to ensure student-friendly educational website visits, Rice University is notresponsible for the content of third-party websites.

For more information, visit STEMscopes.com

Sentence Stems

1. Stem: My diagram represents ___ (Insert example 1 here), because…

2. Stem: My diagram represents ___ (Insert example 2 here), because…

⋆ FavoriteTOPIC Texas Science - TEKS Force, Motion, and Energy GRADE 7th STANDARDS 7.7C

Essentials Engage Explore Explain Elaborate Evaluate Intervention Acceleration All

Question Prompts

test : Preview ElementaryScopes Standards Student Management Assessments

7.7C Forces in Everyday Life

Remember-Recall

What is turgor pressure?

Turgor pressure is the force of water molecules against the cell wall which allows plants to stand

up straight.

Understand-Skill/Concept

How does a plant with high turgor pressure differ from a plant with low turgor pressure?

In a plant with high turgor pressure, the cell walls are firm and straight, and the plant is able to stand up straight. In a plant with

low turgor pressure, the cells lose their shape and shrink, causing the plant to wilt.

Apply-Skill/Concept

How would you explain the effects of turgor pressure in a seed on the seedlings roots and stems?

Analyze-Strategic Thinking

What is the relationship between the direction of the gravitational force acting on a seedling to the direction that the stems and

roots grow?

The roots grow in the same direction as the force of gravity. The stem grows in the opposite direction as the force of gravity.

Evaluate-Extended Thinking

Should you be worried about the direction that the plant stems will grow if you planted the seeds on their sides? Why or why not?

Contents

Remember-Recall

Understand-Skill/Concept

Apply-Skill/Concept

Analyze-Strategic Thinking

Evaluate-Extended Thinking

Create-Extended Thinking

Example illustrations

View As Student Feedback Speech a A

© 2014 by Rice University. All rights reserved. While every attempt is made to ensure student-friendly educational website visits, Rice University is notresponsible for the content of third-party websites.

For more information, visit STEMscopes.com

I should not be worried because the stem will grow against the force of gravity and push through the surface of the soil and

receive light. In the Explore activity, we observed that all of the seedlings began growing the same way. The stems grew up

against gravity, and the roots grew down toward the force of gravity. In the activity, we randomly placed the seeds into the

plaster. Some were pointing up, some were pointing down, and some were on their sides, but all the seedlings still grew with the

stems up and the roots down.

Create-Extended Thinking

How would you design an experiment to determine the effect of turgor pressure on a seeds ability to break through plaster?

Hypothesis: If a seed’s turgor pressure is high, then it will break through the plaster more quickly than a seed with low turgor

pressure. A seed with a high turgor pressure has more force to exert against the plaster in order to break it apart faster than a

seed with low turgor pressure. To test this hypothesis, I would soak three beans in fresh water, three beans in a 4% salt

solution, three beans in a 20% salt solution, and leave three dried beans unchanged overnight. The beans soaked in water

should have the highest turgor pressure, and I would expect them to break through the plaster first. The next day, I would

prepare 12 separate, labeled cups containing plaster of Paris, and place one seed in each cup. I would monitor the seeds

periodically over the next several days to observe how long it takes each seed to break through the plaster.

7.7C: Situations of Force Force, Motion, and Energy

Background A force is a push or a pull that can change the motion of an object. Forces are everywhere. Forces, including gravity, are constantly acting upon plants and can cause them to be in motion. Plants can be in motion just like we are in motion. Plants move when they grow or respond to their environment. Turgor Pressure Water within a plant cell exerts a force, called turgor pressure, which pushes outward on the cell wall. The ability a plant has to maintain a strong upright position and return to the upright position when blown by the wind is the result of force from turgor pressure. When plants do not have enough water in their cells or the water has been removed from the cells, the cells begin to shrivel. They shrivel and collapse because of the reduced turgor force pushing outward on the cell wall. If enough cells collapse, the plant wilts because the force of gravity is greater than the force from turgor pressure. Work is done when a force causes an object to move a distance, such as when water in a plant cell forces a wilted plant to return to its upright position.

High Turgor Pressure

Low Turgor Pressure

Emergence of Seedlings Imagine yourself trapped under a bookshelf. To stand up, you must exert a force on the bookshelf greater than the force pushing down from the bookshelf. Seedlings work the same way. Seedlings can only emerge from the soil when they push upward, exerting a force on the soil that is greater than the downward force of gravity. The turgor pressure inside of the plant cells must be high in order to have enough force to push up on the soil. If the turgor pressure is low, the seedling will not have enough force to emerge and overcome the force of gravity.

Gravity

Seedling

Answer the background questions in the Student Journal.

1

Part I: Turgor Pressure Procedure: 1.  Obtain a potato slice from your teacher. Cut the slice into three potato sticks

that are equal in length, width, and height. They will resemble French fries. 2.  Before placing the potato sticks in the beakers, measure the length of the

potato sticks (figure 1). Record the initial length of all three potatoes in the 0 (Initial) row in Data Table 1: Potatoes in your Student Journal.

3.  Place 1 potato stick in a beaker labeled Water. 4.  Place 1 potato stick in a beaker labeled 4% Salt Solution. 5.  Place 1 potato stick in a beaker labeled 20% Salt Solution. 6.  Start timing and wait 10 minutes. Use a pencil to divide a paper plate into

thirds, and label one third - water, one third - 4% salt solution, and one third - 20% salt solution. Set the plate aside. Complete question 2 in the Student Journal while waiting.

7.  At 10 minutes, use the forceps to take the potato sticks out of the water and salt solutions, and place them on the labeled paper plate. Do not mix up your potato sticks. They will go back into the same beakers.

8.  For each stick, hold the potato piece by the top edge. The bottom edge of the potato will be on the table so that it stands lengthwise. Pull the top edge down toward the bottom edge as far as you can bend it without breaking the potato. Use teamwork to measure the distance from the top edge to the bottom edge of the potatoes (as shown in figure 2), and measure the distance that shows how it will bend without breaking.

9.  Record your results for 10 minutes in the 10 min. row on Data Table 1: Potatoes in your Student Journal

10. Return the sticks to the beakers. They go back into the same beaker that they came out of. Do NOT mix them up.

11. Start timing and wait another 10 minutes. While waiting, continue adding detail and labels to the diagrams of the initial set up of each beaker for question #2 in the Student Journal.

12. After an additional 10 minutes, use the forceps to take the potato sticks out of the water and salt solutions and place them back on the labeled paper plate. Measure the distance, like before, to determine how much the slice will bend without breaking.

13. Record your results for 20 minutes in the 20 min. row on Data Table 1: Potatoes in the Student Journal.

14. Sketch the bend of each potato in the small box to the right of each set up in question 2 of the Student Journal.

Please continue on the next page.

Figure:1

Figure 2

2

7.7C: Situations of Force Force, Motion, and Energy

7.7C: Situations of Force Force, Motion, and Energy

Part I: Turgor Pressure, continued

15. Clean up as directed by your teacher. 16. Complete the remaining questions for Part I in the Student Journal. Part II: Emergence of Seedlings Procedure: 1.  Mix 2 tablespoons of Plaster of Paris with 1 tablespoon of water in a plastic cup. 2.  Stir the mixture with a craft stick. More water may be needed to reach a consistency similar

to a thin liquid glue. 3.  Write your group members’ initials on the side of the cup. 4.  Place 2 seeds in the mixture, and set aside per your teacher’s instructions. 5.  Throw the craft stick in the trash and clean up any mess that may have been made. 6.  Observe your cups daily for any changes. 7.  Keep the top of the dried plaster wet by slightly dampening a piece of paper towel. Fold the

paper towel twice so that you have a double layer and set it on top of the dried plaster. Repeat as needed.

8.  Record your observations in your Student Journal.

Answer all remaining questions in the Student Journal.

3

Background

1.  Define force: __________________________________________________________________________________________________________________________________________________

2.  How does gravity affect objects? __________________________________________________________________________________________________________________________________________________

3.  What forces act on or within plants? __________________________________________________________________________________________________________________________________________________

4.  What is turgor pressure? __________________________________________________________________________________________________________________________________________________

5.  What happens to a plant with low turgor pressure? __________________________________________________________________________________________________________________________________________________

6.  What must a seedling do in order to emerge through the soil? __________________________________________________________________________________________________________________________________________________

Part I: Turgor Pressure 1.  Potato Slices and Turgor Pressure. Record your observations in the table below.

7.7C: Situations of Force Force, Motion, and Energy

Data Table 1: Potatoes

Time (min) Measurement (mm) Distance Between the Top and

Bottom of the Potato Stick. Water 4% Salt 20% Salt

0 (Initial)

10

20

1

Part I: Turgor Pressure, continued

2.  Draw and label a diagram in the large space of each box below that shows the parts of the initial set up of the potato sticks in each beaker.

Water 4% Salt 20% Salt 3.  Sketch the “bend” of each potato stick in the right side of the boxes above after your final

measurement.

4.  Which potato had the greatest amount of turgor pressure? Explain. __________________________________________________________________________________________________________________________________________________

5.  Which potato had the least amount of turgor pressure? Explain __________________________________________________________________________________________________________________________________________________

6.  Draw a picture of what you believe a potato cell would look like under a microscope after being in water and another picture of what it would look like after being in a 20% salt solution.

Water 20% Salt

7.7C: Situations of Force Force, Motion, and Energy

2

7.7C: Situations of Force Force, Motion, and Energy

Part II: Emergence of Seedlings 1.  Describe what happened to the plaster when the seeds began to grow.

___________________________________________________________________________________________________________________________________________________________________________________________________________________________

2.  How does a seedling emerge through the soil? ___________________________________________________________________________________________________________________________________________________________________________________________________________________________

3.  Why is it important for the seeds to be watered. Explain in terms of force and turgor pressure. ___________________________________________________________________________________________________________________________________________________________________________________________________________________________

4.  If the 2 cm seedling was pushing upward with a net force of 12 N, how much work was done? __________________________________________________________________________________________________________________________________________________

5.  If a seed did not have enough force to push through the plaster and did not grow, how much work was done? Explain. __________________________________________________________________________________________________________________________________________________

3

Reflections and Conclusions

1.  How does force affect the motion of plants? ___________________________________________________________________________________________________________________________________________________________________________________________________________________________

2.  Why do grocery stores have water misters in the produce department? Explain. ___________________________________________________________________________________________________________________________________________________________________________________________________________________________

3.  If flowers begin to wilt, is there anything that can be done to save them? ___________________________________________________________________________________________________________________________________________________________________________________________________________________________

4.  Predict what would happen to plant cells if their turgor pressure was too high. ____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

5.  Create a scenario that demonstrates a situation which explains how a seedling emerges from the soil. _____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

6.  Compare the turgor pressure of a cell to a water balloon. __________________________________________________________________________________________________________________________________________________ _________________________________________________________________________ _________________________________________________________________________ _________________________________________________________________________

4

7.7C: Situations of Force Force, Motion, and Energy