Lab14

Magic and Capacitors:

here, applying the basic physics behind a capacitor, we decided to make our own, using aluminum sheets separated by paper.

The same capacitor, with half the area.

The data collected, using factors such as area of aluminum sheets, distance of separation (counted in pages as well as meters) and capacitance achieved.

Look at this beautiful graph! We were able to fit the data to an exponential graph, and boy did it fit nicely.

The formula for the half area capacitor was the same as the previous, except the slope was much steeper.

Capacitors: series vs parallel

we used these capacitors in series and in parallel to observe a relationship between the configuration and the voltage produced. As it turns out, they behave exactly the opposite as resistors do. Meaning that if capacitors are in series you add them inversely (1/Ctot)=(1/C1)+(1/C2), where as if they are in parallel you simply add them up.

And here you have it. The total capacitance of this mess of 5 capacitors...SYMBOLICALLY!

Lab 13

Checking the current (I) in all the junctions of the circuit. The results seem to be proportional as we add a second battery to the circuit. all the values almost doubled, as the voltage (V) almost doubled.

A closeup of small resistors. The top one is older technology, where as the bottom one is a newer model, which also happens to be cheaper.

calculating how resistors add up, both in parallel and in series

A step-by-step process on how to add capacitors, both in parallel and series.

Our calculated value came to be 52.2 Ohms

putting these resistors together was troublesome, but once we succeeded we measured 51.8 ohms. Thats a 98.7% accuracy!

Sloppy calculations on how to find the current in all three parts of the circuit

The results!


Testing the Loop Rule with a real circuit:

The Circuit

The resistance, voltage, and current measured. We then calculated the Current, and got shocking results. The current through the resistor 1 had about half the calculated current running through it... The current through the 2nd resistor was almost as bad, having 68% running through it. The 3rd resistor restored faith in me, showing a 100% accuracy to what we calculated. There must have been some kind of bad connection in some of the wires, because we did have trouble getting the Voltage of resistor 1 and 2 as well.

Showing how to adjust the resistance of the pod.

Lab 12

ELECTRIC POTENTIAL

This is the general setup we used for this experiment. It's a dot of silver connected to 15V power supply with the negative end connected to the silver line. Then we used a volt meter on the semiconducting black sheet to see the electric potential of the system at various points away from the silver dot. 

Our data came out magnificent. The interesting thing to note is that once we measured the voltage distance AFTER the silver line, it's electric potential would drop at a slower rate. 

Plotting the data of electric potential (V) vs distance (x) we observe the graph having a fairly exponential shape 

Lab 11

The Quiz (I missed)

So after a little research and consultation from my class mates, I came to an understanding that we had a quiz. And to the extend of my knowledge it involved creating a circuit with a 2 batteries and a light bulb. The goal was to create a very dim light. And a very bright light. Now I did get upset, because I was working on my Lab 10 blog and lost track of time, resulting in a missed quiz of a subject I love ever so dearly...

Anyways, I did draw the diagram of the circuits on my spare time as you can see below.

The diagram of a dim light.

The diagram of a bright light. depending on how the batteries are connected (either in line or in parallel determines the voltage of the circuit, one having a big potential cliff, and the other a fairly shallow one)

Heating water using 2 different voltages

This picture shows the graphs of the temperature changes of a cup of 200g of water using a wound up coil powered by 4.5V and 9V.

Shown are the temperatures of the water before and after measurement.

Calculating power and Heat using the 4.5V values. This was done theoretically, so we can see if the values line up with the measured values.

Some more very interesting calculations. Calculating Heat, and the change in temperature.

Yay!! The calculated results fall within the actual experimental data!

The uncertainty was done by simply taking the difference between the 2 temperature values and dividing it by 2. Now I'm not sure if this is how its suppose to be done, but deltaT totally comes out to be right.

How scientist cook their sausages..

In this experiment we wanted to see which sausage will get hot sooner, the short fat one, or the longer skinny one. It turns out that the longer skinny one did heat up and steam first. We believe it is due to a greater difference voltage between one end of the sausage and the other end.

Here we can see Master Mason carefully handling the sausage to get a good contact for the small LEDs. The further the contacts are spread apart from one another, the greater their difference in voltage is, and the brighter they shine. In this picture only the middle one seems to be lit, because one burnt out due to overload and the other doesn't have enough of a voltage difference for it to light up.

Lab 10

Volts and Current

Having a simple circuit we establish the relationship between Volts, Current and Power

Running a test with a Ammeter, we understand that the Current is constant throughout the system. (before and after the lap)

Reiterating the statement above, the analogy can be made with the water generator and stream. The water is never lost, it just looses energy.  

Resistance

We used a voltage generator and ran it at different volts. In the circuit we had a coil which had a unknown amount of wire wrapped around it (using it as the resistance). and we were able to find a relationship between Voltage, Current, and Resistance

As seen above the Voltage and Current are directly proportional. The slope of the V-vs-I graph indicates the amount of resistance. The higher the slope of the linear graph, the greater the resistance.

The data collected with different coils, different lengths, and different material. This gives us a good way to determine the relationship of Resistance with either one of those other factors.

Relationships between Resistance and different attributes of a wire.

Lab 8

Electric Flux:

Nails on a board.

For this lab we used a board of nails all pointing in the same direction. Unfortunately we dont have a picture of the actual item..

We used a wire square to represent an area that an electric field will flow though.

Measuring the hight of the tip of the square we were able to get the angle of the incline of the square and plot the data into logger pro.

The angles were used so we can limit the amount of nails passing through the grid.

The results we were able to fit with a cosine curve, indicating a cyclical behavior.

Activ Physics:

A single point charge inside an enclosed area

A point charge outside an area has no flux.