Tuning Fork and Palm Pipe Lab

         Last week we used palm pipes to give us a sense of how woodwind instruments work. In order to produce a musical note, we would hit one end of the open pipe with our palm. Each pipe created a different sound due to their size. With a woodwind instrument, the fundamental frequency is 1/4. We also learned that because the palm pipe had one end closed when the sound wave was produced that there can only be an odd number of harmonics. The pipe that I was given (#9) produced a much lower note than those of my table mates because it was much larger than theirs. The larger the pal pipe, the lower the sound. This occurs because a longer pipe increases the frequency of the wave, while the shorter pipes have a much lower frequency.
          We then struck tuning forks and recorded the sound made with a microphone that was plugged into our lab quests. Our screen showed us a wide variety of frequencies, however the highest frequency was the note that was produced.


Once we recorded the sound waved produced by our tuning fork, our lab quest screen gave us this:

We then clicked "analysis"; "advanced"; "FFR" and finally "sound pressure", giving us a graph like this:

(photos taken by Megan Grealish)

Light & Optics in the Real World

The picture below shows me holding a mirror in front of another mirror. This created a never ending virtual image of me holding up a mirror.

In order to understand how a mirror works, you must also understand the laws and principles of light. When a light hits a surface, it bounces off of that surface at a certain angle. The angle that the light hits the surface, or the angle of incidence, will determine how the light bounces off. Objects like prisms scatter a beam of light and show the entire array of waves that are in the single beam of light (Dark Side of the Moon). However a mirror does not alter the incoming beams of light, instead the light rays bounce back. The image from a flat mirror is a virtual image because it cannot be focused, and the rays are not coming out at straight lines. The rays hit our eyes and enable us to see our reflection, however it is not really there. 

Physics Standard 6.1

Standard 6.1 Question: How is electricity generated by moving magnetic fields? 

In order to generate electricuty, we need electrons to move. Without moving charges electricity will never be created. Usually this is created by a voltage source, a set of wires which creates the current, and obviously a resistor. Examples of resistors that are common in our everyday lives would be things like lightbulbs. In our lab, the moving magnets push the charges- essentially the magnet acted as the voltage source. Because the charges were being pushed, we had the potential to create electricity because we were moving the electrons. This kinetic energy from the magnet turns into electric potential energy, and is then transferred through the wires which create the current and then into the resistor which gives off the light.

Example: Water Wave Generators

-Energy output is determined by wave length, height and speed
-Kinetic Energy generated from waves turns into "Ue"
-Ue goes through wires which transfer the current to wherever the energy is needed

Lemon Battery Lab

Link Regarding iPad Batteries

http://www.pcworld.com/article/2018970/ipad-family-aces-battery-tests-while-android-tablets-lag.html

Overview:

Over the course of this week, I learned about electrostatics (the movement of electrons) and voltage (the measurement of electricity). We had an assignment that asked us to place a comb next to a thin stream of water. We had previously used the comb to comb our hair, which gave it a charge. The comb forced the water to move closer to it, proving that we had charged the comb.

-After the Lemon Battery Lab I got a true feeling for what voltage is. It's simply Electric Potential Energy. Also, when solving equations regarding electrostatics, voltage = height. Voltage is essentially building up this big mountain of energy (which is why it is similar to height), which then gets transfered into other things. An example would be the "mountain of energy" that you built up and transfered when you combed your hair and put it up near the stream of water.

-This analogy on voltage can be applied to iPad batteries too. The newer iPads have much larger batteries, making them more powerful and giving them a longer lifespan. What the larger battery is doing is just creating a larger "mountain of energy" that is used to power the various apps and programs that are running on your iPad. 

Projectie Motion

Brief Description of the Lab:
In this lab we were given the task to find out what the true definition of a projectile is. To figure this out, we went down to the basketball courts and filmed the flight path of a basketball after it had been shot. We were able to find out the acceleration and velocity of the ball in the x and y dimensions.

Vy:

This graph gives us all of the information we need to find the y component of the basketball being thrown. The parabolic shaped graph (top graph) shows us the y position over time, ultimately giving us the value of the slope of the line which is velocity. When looking at the graph you can tell that the slope is not constant, meaning the velocity is also not constant which gives us the idea that the basketball is accelerating.

Vx:

This graph below shows us the x position over the period of time that was taken to record the basketball shot. The slope of this graph is represented by the change in position over the change of time. Unlike the Vy of the basketball, this is constant. THis means that there is no acceleration in the horizontal dimension and that it is constant. 

Photo of my group's whiteboard:

2-D Forces and Circular Motion

1)      To analyze forces in 2D one must find the magnitude (or size) of the x and y intercepts. The x and y intercepts, when in the second dimension, are called Force X and Force Y. In order to find the values of fx and fy you use sin, cos, and tan.

2)      Forces cause objects to move in a circle by pulling them in with a gravitational force. During our hover disc lab, we exerted a tension force (similar to the gravitational force of the earth on the moon), on the hover disc. We learned that the hover disc is being pulled into us but is also constantly accelerating, which enables it to move around us in a circle. A real life example of this would be the International Space Station and its orbit around Earth: Because the tangential velocity of the space station is so great, it does not matter whether or not the space station is in a constant free fall. The station never comes crashing down into the is because we simply keep missing it. There is no air resistance in space as well,  disabling space station's velocity from slowing down.

http://commons.wikimedia.org/wiki/File:ISS_after_STS-124_06_2008.jpg

3)      To be in orbit means that a small object is in a constant circular motion around a much greater object. The larger object is exerting, or pulling,  a gravitational force on the smaller object, which is in a constant free fall (as we learned in the video).  Satellittes orbit Earth in the exact same way. Satellittes are in a constant free fall around the Earth- their velocity is so great that they constantly "miss" the Earth, just as planets do to the Sun.

Newtons 3rd law

Purpose:
The purpose of the Fan Cart Lab was to measure the increase and decrease of acceleration produced by the fan cart on a track that had little to no friction. The force that was produced from the fan cart remained constant,  even though each test had different accelerations. During each of the tests, we increased the mass of the fan cart to see if there would be a difference in acceleration or force. Meanwhile, all of this was being recorded on the range finders.





Data:

After reviewing the data of the lab, we know that the relationship between mass & acceleration is indirect. We also learned a new equation: force= (mass)(acceleration). Finally, we cam to the conclusion that an object will remain in motion unless an outside force is acting upon it, an example in this lab would be someone catching the cart and pushing it. 

Real World Connection:

The connection to the real world with this lab involves my cat, Simba. When he runs around my house, he tends to slide due to the stone floors. The absence of friction makes him slide and smack himself into the side of our walls. The wall and Simba both experience the same amount of force, but the wall is much more massive and experiences no acceleration after the crash, while he lays there stunned. 

Impulse Lab

Purpose:
In this lab we a cart with metal bands attached to its end, into the left end of the track. The metal bands were used to "slow down time". We pushed the red car towards the left side of the track. Because it had a metal band on the end of it, it bounced back. On the computer the graphs were able to tell us the velocity before and after the collision.


Data:
                        Impulse remains constant in a collision      

*Impulse: J=F (force) X T (time)

*Force and time are inversely proportional

*Impulse = area of force vs. times graph

Connection to the Real World:

The first connection I made to the real world would be in any play in water polo. When you are passed the ball, you need to catch the ball with a finess that essentially reduces the force of the pass hitting your hand. By doing this you enable the velocity of the ball to decrease with ease, just like the metal rings on the carts in the lab.

Collisions Lab

In class: 

This week in the collisions lab we were given two carts (one red and one blue), a computer, a track and two motion sensors that were connected to a labquest. We put the two carts on the track and sent them towards each other in two different types of collisions, one elastic and one inelastic. The sensors would send out sonar waves to the carts, and would be able to tell how far away the cart was from the senor at any given second. In the elastic collision, both of the springs on the carts were facing each other, in the inelastic collision, we have the velcro sides of the carts collide with one another.

Data:

MOMENTUM IS CONSERVED

P(total before)= P(total) after

m + v x m x v = m + v x m+ v

The two right columns on the data table explain to us what this equation above really means. As you can see, the amount of momentum decreases, meaning it is conserved.

Connection to the Real World

Any collision from the real world can be applied to this, one that comes to mind is bowling and more specifically when the bowling ball strikes the pins. The collision between the ball and the pins is inelastic. When the two hit one another, the momentum is conserved. This is exactly the same as the inelastic collision we tested during class.

Rubber Band Cart Launcher Lab

In Class:
The purpose of this lab was to calculate and find out the relationship between energy and velocity. In this lab we put a .38 kg glider on an air track, and measured its velocity when it passed through a photogate sensor we had set up about a foot down the track. We pulled the glider back, stretching a rubber band at .01 to .05 m and measured the velocity when the glider was released during each test.  After the testing was completed, we graphed the data and came up with an equation explaining the reasoning behind our graph and its slope: E=1/2mv^2. This equation tells us that the energy of the glider is equal to half of its mass multiplied by the velocity of the glider squared.

Data:

The velocity and energy have a direct relationship:

X and Y coordinates of the graph below

Graph showing the trend and relationship between Energy and the average velocity squared

Connection:
A connection that we can make to the real world is eerily similar to our previous labs connection. Last week we figured out how to store energy in a rubber band, the connection being a bow. However, this week we basically tested the other part of a bow, the arrow. When we pulled the cart backwards, stretching the rubber band back, we were loading up the rubber band with energy. The further we pulled the rubber band back, more energy was stored and the glider would move faster. This is similar to a bow and arrow because the more you pull the string back, the faster the arrow will go- just like the glider and rubber band.

Rubber Band Lab

In class:
The purpose of this lab was to figure out how we can store energy, particularly that of a rubber band. The standard that introduced us to this was standard 3.3. In this experiment we "single looped" a rubber band and measured how much force it took to pull it. We started with 1 cm and increased to 5 cm in increments of 1. After we completed these tests, we ran another experiment but this time the rubberband was looped around the notches two times. After recording the data, we derived the equation Us=1/2kx^2, meaning that the Elastic Potential Energy is equal to half of the elastic constant multiplies by the distance stretched (which is squared).

Data:


Big Questions: "How can we store energy to do work for us later?"

Trial One:  Test One (Single Loop)
1 cm:  Force .39
2 cm:  Force .92
3 cm:  Force 1.31
4 cm:  Force 1.94
5 cm:  Force 2.9

Trial One:  Test Two
1 cm:  Force .38
2 cm:  Force .91
3 cm:  Force 1.25
4 cm:  Force 1.87
5 cm:  Force 2.74

Trial Two:  Test One (Double Loop)
1 cm:  Force 3.1
2 cm:  Force 4.4
3 cm:  Force 6.3
4 cm:  Force 8.0
5 cm:  Force 10.8

As you can tell from the data that my group and I collected, as the distance we used to pull the rubber band increased, so did the amount of force needed to pul it.   

Connection to the Real World:
The strongest connection that I could find to the real world would have to be firing a bow and arrow. The same concept of storing energy in a rubberband applies to this as well. When you pull the string attached to the bow back and get ready to fire your arrow, you are storing energy. Also, just like in the lab if you pull the string further and further back, you will store more and more energy in the bow thus enabling you to fire the arrow for a greater distance.

Pyramid Lab

In Class:
The purpose of this lab was to recognize the relationship between the amount of force used to pull something and the slop that it was being pulled on. In this experiment we pulled a a small cart up a ramp starting with a moderate to minimal slope and then gradually increased the steepness of the slope each trial. While pulling the cart, we had an electro magnetic pro measuring the amount of force it took to carry the cart up the slope. We also learned the equation W=FxD, which perfectly explains the relationship between the amount of work that is put into pulling the cart up the ramp, and the distance.

Data:

Trial 1: 
Distance= 1.5 m
Force= .767 N
Work= 1.15 J

Trial 2:
Distance= .85 m
Force= 1.822 N
Work= 1.54 J

Trial 3:
Distance= .55 m
Force= 3.9 N
Work= 2.15 J

Connection:
A connection that you can make from this lab to the real world can be found on ramps for wheelchairs and in the pyramids of Egypt. The ramps for wheelchairs are at the perfect slope because they do not require much effort to go up one and they are not too long either. The pyramid's ramps had the same properties as the ramps used for wheelchairs, they were moderate enough that you could pull or push something up them but at the same time they required very little distance.

Pulley Lab

In class:

The purpose of this lab was to recognize the relationship between the amount of force used, and the distance used to lift a certain mass. To lift the mass we created pulley. Lifting the mass with the pulley used much less force than without one, which resulted in the final thought that more distance = less force. This is because work remains constant. To graph the two different tests, we used a bar graph like the one shown below. In the graph, we show the relationship between force and the distance used to pull the mass. As the amount of force used increases, the distance is much less. The equation we created from our information is A=FxD, meaning the area shaded on the graph is the result of the amount of force used multiplied to the distance used as well.

Connection to the Real World:

You can connect the information found in the lab, and doing simple tasks that involve something like a hammer. A hammer is similar to this because you are adding distance to the swing you use to hit a nail down into a piece of wood. Heres an example: Try hitting a nail with your hand, and then try hitting one with a hammer. Hitting the nail with the hammer is much easier because the added distance takes less force (it also doesn't destroy your hand). 

Mass vs. Force

In class lab:

Ex.

The purpose of this lab was to learn the relationship between force and mass.  My group and I massed various brass cylinders. We learned that the force being exerted on these objects is equal to the mass multiplied by the gravitational constant. Also, to graph the data recorded we used a best fit line. My group and I put the mass of the objects on the y- axis, and the force used on the x- axis. After the experiments were done, were derived the equation "F=MxG" from the graph.

Connection:
Something similar to this can be found in golf. When you strike a golf ball with the head of your club you exert force onto the section of the ball which you hit. Once the ball is hit, the force given off by the ball is equal to its mass multiplied by the gravitational constant     (10 N/kg). To make the ball move further, you need to add more force and speed into your swing. The golf ball eventually falls down because earths gravitational constant is pulling it back to the ground.