Lab: Modeling friction force
Group members: Michael Flores , Alex, and Michael
Purpose: Five different experiment involving friction
Theory: Use a block and mass to help find the friction forces
Apparatus: For this experiment we attach a block with a string on a level surface. The string went through a pulley and added weights until the block move. We then use an incline for the block and perform the same thing from when the block was at a level surface.

For the first experiment we were able to get the static friction max by adding masses to the string that runs through the pulley. We perform the experiment 4 times here are our results.
Then we graph fs max as the y axis and normal force as the x axis to get the static friction

The 2nd experiment was use to find kinetic friction. We attach the string connect to the block to force sensor. Someone then pull the string and were able to get fk max. Then we ploted a graph as fkmax as the y axis and normal force as the x axis to get the kinetic friction.

For the third experiment we added an incline at 25 degree. We the perform the same experiment as of the first one, but with an angle. Here a way of how to get the static friction from the data.

For the fourth experiment we use the incline at a 30 degree angle and added the sensor at the top. We then put block on the incline. The block slid down and we were able to get the kinetic friction.

For the fifth experiment we use the kinetic friction of the fourth experiment we will be able to derive an equation to get the acceleration. The acceleration end up being 0.88

Lab 4: Modeling the fall of an object falling with air resistance
Group members: Michael Flores, Alex , and Michael
Purpose: determine the relation between air resistance force and speed.
Theory: Use the data we recieve from drop the coffee filter to get the velocity
Apparatus: For this lab we drop five coffee filters, one at a time from a balcony inside a building. We recorder the fall from each filter and use logger pro to help plot the points to form a position vs time graph. Then we use excel by applying a mathematics model to recieve the velocity.

The y axis was use for the position, while the x axis is for the velocity. To get the air force  we have add up the function of the shape and the speed. We were able to get the velocity from the position and time. The air resistance was the mass times gravity. We then graph the air resistance as the y axis and the velocity as the x axis. Their were uncertainties for both values.

Here is the equation we use.

Then we use excel.

Excel work the way wanted but there was a number that was way off from the others that concern us.

Lab: Trajectories
Date perform: September 14, 2016
Lab group: Michael Flores, Alex, and Michael
Purpose: Use projectile motion to predict the impact point of a ball on an incline board.
Theory: Derive an equation for trail without the board to find the velocity to help find the distance for the trail with board.
Apparatus: In this lab we made a ramp with metal poles for a marble on the table. Then we roll down the marble to see where it impact the floor. We had a carbon paper to get a accurate measurement where marble hit the floor. We then use a plumb ball to measure the height. After that we did the same thing, but added a wood board and made sure the marble impact on the board. Here a picture of the lab we did.

The measure we obtain without the board were a height a 94.2 cm where the ball was launch at and a distance of 78 cm from the table. To determine the launch speed, we did this:

Then we added the board and tried to find the distance of the impact. we were able to get the distance with theses calculations:

The distance of the marble from the board and with out the board were very similar. Both of their height were the same and the X distance were off by less than six centimeters. For both trials their would be uncertainty by 0.001 meter form the height and distance from the table. 



Lab: Non constant accelerating activity
Date perform: September 7 2016
Purpose: Find the distance of the elephant before coming to a rest.
Theory: We were given time and from Newton second law were able to find the acceleration. Then from acelartion and time we can get velocity. After that we should have all the tools to obtain distance.
Apparatus: In this lab we were given a problem that a 5000kg elephant with roller skates. The elephant had a rocket on its back that was generating a constant thrust opposite the elephant direction of motion. We had to find the distance before coming to a rest. So with numbers given we plug them in excel.


From the time we were able to plug it in Newton second law equation to find acceleration. From acceleration we added the one before and current acceleration and divide it by two to give us the average acceleration. We multiply the average acceleration with time to give us the velocity. Then we added the velocity with initial velocity, divide it by two to give us average velocity. Lastly, we multiply the average velocity with time and were able to get the distance.
Doing the problem analytically save us a large amount of time compare to numerically. We were less likely to make a mistake analytically, and if we did it would be much easier to fix.
Here is the equation we receive from Newton second law to find acceleration.

Lab 6: Propagated uncertainty in measurement
Date performed: September 7
Lab group: michaelflores, Alex, and Michael
Purpose: Intorduction to propagated error calculation
Theory: measure the density of metal cylinders to find propagated uncertainty
Apparatus: For this lab we measure the weight and length of two metal cylinders. We measure the length of the cylinders with metal object called a caliper. Then we took the partial derivatives of the measurements.



As you can see in the pictures we took the partial derivative of the height, mass, and diameter to form an equation for the uncertainty. Then we plug in the numbers and we were able to get accurate answer for both cylinders.

4-sep-2016 Finding relationship between mass and period for an inertial balance

 
Purpose: Find the relation between the mass and periods for inertial for an inertial pendulum equation that predicts well.

Theory: Use the model to form an equation

Apparatus: What we did is at a piece of tape at the end of a metal tray. The tape passes through a detector to measure the period. We added 0 to 800 grams to the trays. We added 100 grams at a time.

This is the result we obtain from the trials. As you can see the more weight added resulted to an longer period.

Then we were given the power law equation: T=A(m=Mtray)^n. We took the natural log from each side to get an equation similar to y=mx+b. the equation is InT=nIn(m+Mtray)+InA

InT is the y

nLn is the slope

(m+Mtray) is the x

In A is the y intercept

Plunging in the numbers from the date table was able to form a data set.

From this date set we were able to plot a graph

We had to plug in numbers to figure out Mtray. To figure out if the number of  Mtray were right, the graph should have an straight line. The correlation had to be as close to 1 as possible. For example my team graphs were 0.9998. There was uncertainty with the mass because multiple numbers contain the correlation of 0.9998. So my group ends up have a range of 280 grams to 290 grams.

From that we have done so far we were able to form an equation: [T/A]^1/n-Mtray=m

We use two other objects to test out the equation

First was the phone

The period of the phone was 0.407 and the actual weight was 18g

Golf ball period was 0.324 and weigh 45g

By using the equation were able to find a weight but the masses were nowhere near the actual weight. The equation had the masses of the phone and golf ball very similar.

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