I. Title: See Saw Science

II. Problem: What is the relationship between distance and weight for a balanced

seesaw?

III. Materials: a meter stick, masking tape, 28 pennies minted after 1982, a small object

with a mass of about 50 g, a marker

IV. Procedure:

1. Begin by getting the meter stick and the marker and place the meter stick above

the marker. The meter stick will be placed on the 55cm mark above the marker.

2. Then slide the 50-g mass along the shorter end of the meter stick until the meter

stick is balanced, with both sides in the air.

3. Copy the data on a paper.

4. Place a stack of 8 pennies exactly over the 8-cm mark. Determine the distance, in

centimeters, from the pivot point to the pennies. Record the distance this distance

in the “Distance to Pivot” column for the right side of the seesaw.

5. Predict where you should put a stack of 5 pennies so that is balances out. Test to

see if your prediction is true or not. Once you know what the actual position is

then write it down on “Position of Pennies” column for the left side of the seesaw.

6. Determine the distance, in centimeter, from the picot point to the lift stack of

pennies. Record this distance in the “Distance to Pivot” column for the left side of

the seesaw.

7. Multiply the weight of pennies by the distance to the pivot point. Record the

result in the last column of the data table. Predict how the position of the pennies

in step 5 would change if you used 7, 12, 16 and 20 pennies instead of 5 pennies.

Test your predictions

V. Data:

Pivot point position: 55cm

Trial side of weight of position of

distance

to weight of

number saw

# of

pennies Pennies (cm)

pivot

point(cm)

pennies X

distance

1 right 8 80 25 200

left 5 20/14 41 205

2 right 8 80 25 200

left 7 20/26 29 203

3 right 8 80 25 200

left 12 35/38 17 204

4 right 8 80 25 200

left 16 45/42 13 208

5 right 8 80 25 200

left 20 51/45 10 200

VI. Analyze and Conclude:

1. In this experiment, what is the manipulated variable? The responding variable?

How do you know which is which?

2. As you increase the number of pennies on the left, what happens to the distance at

which you must place the stack in order to balance the meter stick?

3. What conclusion can you draw about the relationship between distances and

weights needed to balance a seesaw?

4. Why was it important to zero the meter stick with the 50-g mass

VII. Answers:

1. Manipulative variable is the number of pennies on the left side. The responding

variable is the distance to pivot. By changing the number of pennies, the distance

will change. They are both different.

2. The distance to pivot point decreases.

3. As weight on the opposite side increases, the distance from the pivot point

decreases.

4. Because if you had not put another object of about 50 g on the right hand side,

you would have to add weight to both sides in order for it to be equal. You

wouldn’t have to change the distance of the amount of pennies to the right.

I. Title: A Paper Screw

II. Materials: a straw or a pencil, paper, and a straw

III. Procedure:

1. Get your straw or pencil and measure its length.

2. Cut a piece of paper in half so the paper is in the shape of a triangle.

3. Grab your piece of paper and wrap it around your pencil or straw.

4. Measure the length of the wrapped part of the pencil that is made of paper.

IV. Data: length of straw or pencil: 20.5 cm and length of straw after rapped with paper: 15.5

V. Analyze and Conclude Questions:

1. How does this model represent a real screw?

If you make a second screw then repeat steps 1– 4 and answer this next question.

2. How does this screw compare with your first one?

VI. Answers:

1. The paper wraps around the pencil showing how a screw works and how it is a simple

machine.

2. It should be shorter in the length of the paper around the pencil or straw.

I. Title: How high does a ball bounce?

II. Problem: To see how the height of an object is related to its potential energy.

III. Materials: a tennis ball, a basketball, a meter stick

IV. Procedure:

1. Measure the tennis ball to 100 cm on the meter stick.

2. Drop the ball and catch it. Do this 3x and record the average of the three trials.

3. Do steps 1-2 from 75 cm, 50 cm, and 25cm.

4. Next, get the basketball and repeat steps 1-3.

5. Compare both the basketball and the tennis ball.

V. Data: Table A

Height of tennis ball (cm)

height of tennis ball after bounce (cm)

trial 1 61 Average

100 2 60 61.3

3 63

trial1 40

75 2 45 42.3

3 42

trial1 55

50 2 57 56.7

3 58

trial1 13

25 2 11 12

3 12

Table B

Height of basketball (cm)

height of basketball after bounce (cm)

trial 1 72 Average

100 2 72 71

3 69

trial1 59

75 2 55 56

3 54

trial1 38

50 2 35 36

3 36

trial1 11

25 2 9 10

3 10

VI. Analyze and Conclude:

1. At which measurement did the tennis ball bounce the highest?

2. At which measurement did the basketball bounce the highest?

3. Which ball bounced the highest?

VII. Answers:

1. At the 50 cm mark.

2. At the 50 cm mark also.

3. Overall, I think that the basketball bounced the highest.

I. Title: Can You Feel Power?

II. Problem: Can you change your power while exercising?

III. Materials: a step, a calculator, and a watch with a second hand

IV. Procedure:

1. Copy the data table on your paper.

2. Now go to a stair case and measure the height and record it on the column that

says “height of board”.

3. Assume your weight is 400N and your partners weigh 425N and 450N. Record

the data.

4. Next, calculate the work you do in stepping up onto the step once. Then calculate

the work you do stepping up onto the board 20 times. Record both answers on

your data table. Work = Weight X Height.

5. Step up onto the board with both feet and then, step backwards off the board onto

the floor. This up and down motion is one repetition. Make sure you are

comfortable with the motion.

6. Have a partner time how long it takes you to do 20 repetitions performed at a

constant speed. Count out loud to help the timer keep track of the number of

repetitions. Record the time in you data table.

7. Calculate the power over 20 repetitions. Power= Energy transferred /Time.

Predict how your results will change if you step up and down at different speeds.

8. Repeat steps 6 and 7, but climb the step more slowly than you did the first time.

Record the new data in the Trial 2 row of your data table.

9. Switch roles with your partners and repeat steps 3-8 with a different weight from

step 3a

V. Data:

Trail

Weight(N

) Height of Time for 20

work for

1 work for 20 Power (J)

board(cm

) reps. (cm) rep. (J) reps. (J)

student

1,1 400 0.19 38 76 76 2

student

1,2 400 0.19 19 76 76 4

student

2,1 425 0.19 22 81 81 3.7

student

2,2 425 0.19 14 81 81 5.8

student

3,1 450 0.19 21 85 85 4

student

3,2 450 0.19 16 85 85 5

VI. Analyze and Conclude:

1. What is the gravitational potential energy gained from stepping up onto the

board? How does this compare to the amount of work required to step up onto the

board?

2. Compare the amount of work you did during your first and second trials.

3. Compare the power during your first and second trails.

4. Did you and your partners all do the same amount of work? Did you all do work

at the same rate? Explain your answers.

VII. Answers:

1. As the weight changed, the work changed. The second trial was slower than the

first.

2. It was the same except the amount of weight changes the answer.

3. The second one was larger than the first because it was faster.

4. No, because the weight was always different. No because we all did it differently

in our own ways. We all had a different pace.

I. Title: Separating Mixtures

II. Purpose: To use the physical properties of various substances to separated a mixture.

III. Materials: mixture sample, magnet, filter paper, a funnel, a beaker, and a hot plate

IV. Procedure:

1. Take sulfur, iron filings, and salt and put a magnet on top of the sulfur and salt.

2. Once you have collected all the iron filings, get the beaker and the funnel and the

filter paper and pour water into the funnel which has filter paper on it. Wait so

that the salt water is all in the beaker.

3. Take the hot plate and boil the water so that you have the salt left.

V. Data: Seen by Mr. Snyder.

VI. Analyze and Conclude:

1. What physical properties were used to separate the mixture sample?

2. Were you able to separate the entire mixture sample?

3. What would you do to ensure that the entire mixture was separated?

VII. Answers:

1. Magnetism, size, heat

2. Yes

3. Must be the exact number of mass

I. Title: Measuring Matter

II. Materials: 5 regular shaped objects, 5 irregular shaped objects, a ruler, a beaker, and

water

III. Data:

Mass

Name Mass(g)

eraser 25

black box 12.1

planner 246.5

notebook 314

black top 4.4

screw 7.9

glue top 3.9

pen cap 1.2

plastic cap 0.8

book 102.5

Volume

Name Volume (cm3)

eraser 18.7

black box 11.3

planner 344.1

notebook 422.4

black top 5

screw 5

glue top 10

pen cap 6

plastic cap 1

book 14.05

Density

Name Density(g/m3)

eraser 1.3

black box 1.1

planner 0.7

notebook 0.7

black top 0.9

screw 1.6

glue top 0.4

pen cap 0

plastic cap 0.2

book 0.8