In Class Worksheets

Friction Lab

Key Question Experiment 1: How is the friction force affected by how hard the surfaces are pressed together?

IV: Fn
DV:Ff
CV: Velocity
Secondary Experiment: To find out if the surface material affects the force of friction
Prediction: I predict that if you add more mass to the block you will add more pressure from the block to the surface and the friction force will increase.
Apparatus List: A surface, a block with felt on one side and  rubber on the other side, lab quest mini, a computer, dual range force sensor, masses.

Procedure: First we have to weigh the block with the felt and rubber on it and convert it to newtons.
Then we will attach the block to the dual range force sensor. Then we will drag the sensor at a constant speed to test the force of friction.When you pull the sensor, the block will be rubbing on the table surface, which is how we test the force of friction. We will continue to add weights on top of the block, repeating the same process as before while recording the friction force. We will do this for both surfaces, rubber and felt.
Experiment 1.A: Felt Surface

Data Collection/Data Analysis: 

Normal Force(Newtons)	Friction(Newtons)
.631	.1674
.839	.2068
1.6	.4114
2.6	.5423
3.57	.6452
5.54	1.295

Friction Force Vs. Normal Force

VM: As the normal force increases, the force of friction increases linearly.

MM: Ff=(.2174 N/N)Fn +.0078N

Slope: For every 1 N added to the Fn, the Friction Force increases .2174 N.

Y-Int: When the Fn is at 0N, the Friction Force is .0078N

Experiment 1.B: Rubber Surface

Data Collection/Data Analysis: 

Normal Force(Newtons)	Friction(Newtons)
.63	.8481
.839	1.172
1.6	1.576
2.6	2.604
3.57	3.409
5.54	4.527

Friction Force Vs. Normal Force

VM:As the normal force increases, the force of friction increases linearly.
MM: Ff=(.804 N/N)Fn + .322N
Slope: For every 1 N added to the Fn, the friction force is .804 N.
Y-Int: When Fn is at 0N, the friction force is .322 N.

Velocity Experiment: How does the velocity affect the force of friction?
Force of Friction vs. Velocity
IV: Velocity
DV: Ff
CV: Fn(mass), Surfaces
Procedure: First we will measure the block's mass to get the normal force. After finding the normal force, we will pull the block at various speed to see if it affects the force of friction. During the experiment we will keep mass and surface material the same. 

When we tested if velocity affected Ff, we found out that velocity had no effect on the Ff.

Surface Area Experiment: How does the surface area affect the force of friction?
Force of Friction vs. Surface Area
IV: Surface Area
DV: Ff
CV: Speed, Surface Material
Procedure: First we will measure the surface area of each side of the block. After we know how much surface area each side of the block has, we will test the force of friction on each side of the block by pulling it with the force dual sensor. During the experiment we will drag the block at a constant speed and keep the same surface material.
We found out that surface area has no effect on force of friction.
where is my graph?
Conclusion: 
       In this lab we had to test how various actions would affect the force of friction, we found out that only changing the amount of pressure on an object will affect the force of friction.and the surface material! Changing the velocity and surface area do not affect the force of friction. In the big picture, this will really help us because now we know that only applying more pressure will the force of friction change.equation?  what is slope called and what does it mean?

       Everyones graph had roughly the same graph plot because all the experiment were done the same way. that means everyone should have had the same data, but of course we have to consider human errors as well. my prediction was correct that if you do add more mass to an object, its force of friction will increase.
       It is possible for two people wearing he same shoes to have the different forces of friction because they can both weigh different meaning the force of friction will change. people wearing different shoe can have the same force of friction because maybe their weight to surface material friction could be the same. only pressure given on the object will change the force of friction, not surface area or velocity.
       One error was that someone couldn't pull the sensor at a constant speed. and one other error could be if the block weighs differently or the surfaces had different frictions.

This lab was really fun and i learned a lot from the experiments.

Force Vs. Mass Graph

Force Vs. Mass

Data Analysis:
 VM:As the mass increases, the force increases linearly.
MM:Force=(9.8985Newtons/Kg)Mass - 0.0171 Newtons
Slope: For every 9.8985 Newtons, the mass increases 1 Kg
Y-Int: When the mass is 0 Kg, the Newtons is -0.0171 the force is -0.0171 N - and is it really?  Does that make sense?

 Claims/Evidence: 
Mass is different than weight because mass is the amount of matter the thing has, mass will not change wherever you are,  in space, on the moon, etc, but the weight changes because it is how much gravity is pulling, and gravity is different on other planets and in space than the Earth's gravity. Gravity is also the same around the world and no place has more gravity than other places. There is also the same force of gravity for everything regardless of mass.No  - force of gravity is dependent on mass - see graph.  The field strength is the same We tested this out in class when we dropped the ball and the textbook and they fell at the same time and hit the table at the same time. There is also air resistance, but the gravity is still the same.the force/mass ratio is the same

Conclusion:
 I conclude that gravity has the same force all over the world. When i compared graphs with my peers who also performed the same experiment, we all  had very similar graphs. This happened because the force of gravity is the same on all parts of Earth. We found the equation Fg=MG. Fg is the force of gravity(weight), M is the mass, and G is the gravitational field strength force. This equation could work to find any
 weight by plugging the necessary elements in.
yes but just be careful on wording - force of gravity is weight, and of course everything does not weigh the same...
Data Collection:

Mass(kg)	Force(N)
0.06	0.5865
0.07	0.6765
0.1	0.9665
0.15	1.463
0.25	2.456
0.55	5.429

Dueling Buggies Lab

Dueling Buggies Lab

Objective Statement: We are looking for when a fast buggy and slow buggy intersect at a certain distance at 180cm. One buggy will start at 180cm and go in a negative direction at a fast pace and one buggy will start at 0cm and go in a positive direction at a slow pace.

Procedure: We will first, measure the speeds of the buggies using our phone as timers and a meter stick to measure distance. After we get the speeds of the buggies, we will then place the fast buggy at 180 cm and the slow buggy at 0 cm. We will then start the buggies at the same time and see if they intersect each other at the same place it says graphically.

Data Analysis:

Slow Buggy (100cm)	Fast Buggy (100cm)
5.97sec	2.74sec
6.36sec	2.49sec
6.47sec	2.44sec
Average: 6.27sec	Average: 2.56sec
100cm/6.27sec=15.95cm/sec	100cm/2.56sec=39.06cm/sec

Now that we figured the speeds of the buggies, we found out graphically where the two buggies would meet if we placed the fast one at 180cm and the slow one at 0cm. We made the fast buggy's slope negative because it is going in a negative direction and made the Y-intercept 180 because the starting point is 180cm. good!

After we graphed the equations, we found out that the buggies would intersect at 52.191cm because that is the Y-value where the lines on the graph intersect.excellent!

After we tested graphically, we tested with the actual buggies. The buggies met at a very close point to 52.191cm.

Conclusion:

I conclude that the buggies met at a close enough point to where it was the same as the graph. We may have had problems like reaction time and the straightness of the buggies, but in general the buggies met maybe only 1 or 2 cm from exactly 52.191cm. The lab was very successful.great job!

                                                                                                                                            

Buggy Lab

Pre Lab observations:
Stays in straight line
moves
noise
has
lights
flowers
wheels
red
forward only
keeps going
two seats
Objective: Find what's the relationship between position and time.

Procedure: Our plan is to time how long it takes for the buggy to travel in intervals of 50 centimeters ending at 300. we will use our phones as timers and a meter stick to measure the distance. for trial 2 we will add a 500 gram weight to the buggy and conduct the same experiment as trial 1.



Trial 1(No Weight)

Trial 1 No Weight (370 Grams)

Y-Variable (Position)	X-Variable (Time)
0 cm	0 seconds
50 cm	.67 seconds
100 cm	1.60 seconds
150 cm	2.55 seconds
200 cm	3.28 seconds
250 cm	3.95 seconds
300 cm	5.52 Seconds

VM: As the position increases, the time increases proportionally.

MM: position=(55cm/sec)time + 10.067cm

Slope: For every 1 second the position increases by 55.75 cm.

Y-intercept: When the time is zero seconds, the position 10.067cm. might want to round these

Trial 2(with a 500gram weight) 870g Total

Trial 2 Weight Added (570 Grams)

Y-Variable (Position)	X-Variable (Time)
0 cm	0 seconds
50 cm	.81 seconds
100 cm	1.78 seconds
150 cm	2.75 seconds
200 cm	4.10seconds
250 cm	5.96 seconds
300 cm	5.52 Seconds

VM: As the position increases, the time increases proportionaly

MM: Position=(50.094cm/sec)time + 6.9cm

Slope: For every one second, the buggy travels 50.094cm

Y-Intercept: when the time is 0 seconds, the position is 6.9cm

Claims/Evidence: The slope shows the velocity of the buggy. the y intercept showed where the buggy started. the buggy should have the same velocity because all of the buggys are similar.

Conclusion: I conclude that the buggy traveled at a constant speed. We saw that the slope of both our trial 1 and 2 were proportional because the trend line was linear. more evidence to support that the buggy is at a constant speed, is that we added weight to the buggy and the trend line was still linear. some errors in our lab could have been reaction time because our y intercepts were not 0. i liked this lab because we got to experiment with the buggies and see how fast they went. i also liked that we got to learn new terms like displacement and velocity. it was a god intro to physics for me.  good job!  Just use proper capitalization - it's a formal report. ;)

Earth-Moon Lab

To find the distance from Earth's moon to Earth, i researched online what scale the distance might be. i found out that the distance was 30x the diameter of the Earth, and Since our Earth and moon were already scale to the real Earth and moon, we simply measured our Earth paper 30x away from our paper moon to show the distance in scale from Earth to its moon.

Scientists found out the distance to the moon from earth was 30x the earth's diameter because the distance to the moon is 384,400km. The earth's diameter is 12,756km, and if you divide 384,400 by 12,756, you get about 30. so technically if you lay out 30 earths, you get the distance from Earth to the moon.

Very nice!!  :)