Day 16 Lab 04/28/14

RC Circuits:

Now with the prior knowledge of the resistors in the circuit and how they interact in the circuit. And now with the introduction of capacitors in the circuit we can see the way in the loop  how each of the variables are changed while in the circuit. But now with the introduction of the capacitors in the system and know has to use the energy part of the capacitors because when placed in the circuit it stores up energy and then dissipates causing some energy to be moved onto the circuit causing different values to other components of the circuit.

This is the demo set up which shows the capacitor in the circuit as a result cause the light to be bright  at first but as time progressed the light dimmed down saying the current went to zero. The capacitor stores up energy so when it was removed from the power supply it was able to use the stored up energy to light the bulb.

The same experiment as the image prior but this time has 2 capacitors which made the time for the bulb to dim to be longer because it has places to store up energy.

This a schematic of the circuit being tested on by the demonstration and placing the resistors in parallel and then in series circuits with energy source.

The lab set up of using the capacitor to be connected with a voltage supply causing the capacitor to charge up and using logger pro to see the affects of the charging and the discharging of it. With the graph we can see the distinction between the time amount needed to discharge and charge.

The graphs show the relationship of the potential of the charging and discharging verses the time it takes to both and we see the discharging of the capacitor in red color and charging in the blue which as a result we can see that they are inverse from each other the value of C for the more accurate charging which is a representation of Toa=1/RC in the equation V=Ve^(-t/RC) and q=CE(1-e^-t/RC). The graph is a representation on why these equations are used because the charge can be determined by using the variables we had like time and capacitors can see which is more accurate to use.

A schematic of the experiment of the charging and discharging of a capacitor and can be used to calculate a result to verify our value that we got using the graph. We also used a voltmeter to determine the voltage that was stored up into the capacitor and then discharged.

Using the equation we received from the graph and determined the physical meaning of each part of the equation using the known values to plug into the equation we know the find the values we wanted. The values we received was close to what we calculated and were off by a small percentage in error, and we that the possibilities of error was the misreading of the voltage of the capacitor or a malfunctioning of the data collecting but since

This is an example worked out during class using the known knowledge we obtained from the new equations proven by the lab we can find the values of the charge and the time it takes. The calculations we need were found with the relationship between the voltage and the capacitance.

Day 15 Lab 04/23/14

Capacitance:

In this lab experiment we used an experiment to find the relationships capacitance has in order for it to have a proper value for example area and distance between each plate. By placing sheets in between pages of a book we were able to tell how the distance can either change the values or the stay same as well as the surface area of the sheets used to complete the calculation. After obtaining the values using a graph can place an image to the relationships between the distance of the plate and the capacitance. As a result knowing capacitance, we can place capacitors in a circuit along with resistors.

This is the lab experiment of finding the capacitance by using the equipment in the image and by applying the area of the sheets made and the number of pages (distance) to calculate the capacitance of the system.

These are the values obtained by doing the experiment of the image above and finding the relationship of the different variables that can affect the capacitance.

These are the same values of the image above but placed on excel to make it more readable but also to make a graph to view the relationship between the variables of the capacitance. By using excel it made the calculations easier and can make adding new values easier to be place in the calculations.

This is the graph made by the values and it shows that our graph is incorrect compared to the actual graph image in which it should of been vice versa. The reason we believe for making a wrong graph is because we recorded the wrong values or not placing the sheets in the appropriate amount of sheets. But we mostly believed that our multimeter was giving off readings because most of the time the number will fluctuate and not give a some what actual reading that will stay but had no time to figure out the problem and fix it to make the graph what it should been, an exponential growth. 

This was just a demonstration of showing how a capacitor can explode by placing more voltage than it can hold or an other thing can blow the capacitor. However it also showed what's inside the capacitor which we saw was paper and foil material in order to conduct charge.

After learning about capacitors and their effects we can now see the effects it has when placed in a circuit along with an energy source and some resistors. After some trials done we saw that capacitors are opposite from the resistors in a circuit when trying to reduce to an equivalent resistance or capacitance. Resistors in a series are added up together and while in parallel the parallels are added in inverse to find the equivalent resistance. However, capacitors store up energy, are the opposite when placed in a series or parallel circuit because when in series the inverse values are added up and in parallel the values are just added up. As a result causes complex circuits to be more of a difficult when trying to find the equivalence to make the circuit more easy to make. 

Like the resistance experiment a day prior we placed capacitors in a circuit which included series and parallel and be calculated before measuring to see if the theory does work. And after we measured the values of the capacitance we saw the vales were the same proving that the way of finding the equivalence is legitimate.  

We were given a capacitance circuit in which we had to find the equivalence to make it easier just like the resistors problem and now by using the new knowledge obtained in the experiment we are able to make the problem easier and be able to make the difference between the resistors and capacitors in a circuit.

Day 14 Lab 04/16/14

DC Circuits:

In this lab we used our prior knowledge on circuits to continue to build on by adding resistors into the circuit. The circuits can be simple or complex with many variations of series and parallel circuits with resistors. In a conceptual problem in circuits we must find equivalent resistance in complex circuits to make them easier and be able to make the problem an easier one. Throughout the experiments in the lab we learned how the resistors work, building a circuit, and being able to make complex circuits into simple circuits.

This is the lab set up to make the light bulbs as dim as possible by making a parallel circuit with the batteries and series with the bulbs to keep the bulbs dim.

By using a voltmeter in a circuit we can use many tools that it has to measure many values of a circuit like the current, resistance and the voltage. Now with the new knowledge of using the tool we were able to do the activity in the image below showing the different circuits.

This is the activity when we place the voltmeter in the circuit when making a series with one and two batteries, and also a parallel with one and two batteries. The image shows the values of what the reader gave when place in the circuit looking for the values.

A circuit with the battery and the light bulbs in parallel causing the light of each bulb to have the same brightness proving that it is a parallel circuit.

The calculation or understanding of reading a resistor using the colors on the resistor and be able to see the actual value of the material.

However to the statement of the image above the colors give the actual resistance of the circuit but when measure using the equipment it didn't come out to the actual value because of the internal resistance and other properties.

A problem showing a complex circuit of having both a series and parallel in it and now being able to use what we learned to make the circuit easier by finding an equivalent resistance to make it easier to read and solve.

Using a loop to make the circuit easier to read and find the missing variables using differential equations in order to complete the circuit.

Able to use the calculator to find the missing current values in the circuit using the loop, nodes and power supply with the prior knowledge and saw how the DC circuits are ran to work.

This building the resistance using the resistors to prove the value we calculated in a few images prior in order to actually measure it and prove that it holds truth to using tricks like finding equivalent resistance and find the value that was measured.

Day 13 Lab 04/14/14

Electric Potential:

In this experiment we discussed how the charge can move around a charged ring where we can find a solution by splitting the problem into parts. The potential difference between the potential conductors was determined . It can tell whether or not that if there was work done because the graph is to show the difference of the potential. It can be found in different situations in finding the potential like a point charge pertaining to a ring, sphere, disk and wire, which can be definite or infinite.

This is the calculations of the problem with a charged sphere were we tried to find the voltage potential by moving the charge to different parts of the ring.



The calculations from the image above

This is the potential of dipole charges with the fields being split by a straight line and then making equal forces lines that go around the charges. It is just like the electric fields.

This is the lab set up in which we had to find the electric potential using the chart by moving away from the circle to beyond the line, with power supply being 15 V. However when we did the experiment our results were off by the graph either because of the wrong readings or malfunction of the equipment. The experiment shows that distance is a factor when relating to electric potential and the farther it is from the point, the greater the value from each of the points.

This the graph from the experiment from the image above showing that our values were off causing the graph to have no shape from the actual value. The graph shows the difference between the lower and high potentials and was different from the other groups because it was supposed to show that the change of the voltage is zero.  





Day 12 Lab 04/09/14

Electric Circuits and Potential:

In this lab experiment we were to make a circuit to be able to make a light dim and the other groups brighter just by the way or rearranging the wires and the elements of a circuit. Another experiment we did was putting a heater with resistance in  water cup and calculate the variables needed to find the voltage potential. And the last experiment was seeing the actual relationship with the length and power given because when the LD light had a bigger distance between wires we expected the light to be more bright due to the larger electric potential.

In order to make the bulb as dim as it can possibly can we arranged the circuit by placing the batteries into parallel and the bulbs into series as shown in the image. We were able to use the prior knowledge to have an understanding why certain positions in the circuit can have a different outcome in current and voltage.

The next part of the lab was by placing the heater in a water cup and using what was given at first to find the resistance which then we were able to find the voltage potential. Also how when the voltage changes the whole numbers in the calculations change because each one has a different current.

This image shows the calculations of the experiment were it was used to find the rest of the values by finding each value to find the other values in the system. Then the voltage changed by being doubled causing the numbers to change not just by doubling each value, which was apparently not and shows the relationship with mass and potential. 

This shows the uncertainty of the calculations from the image above which shows that the inconsistency was in with the mass of the water and the amount of power. 

This is the image of the graph from the experiment showing the difference in potential for the ten minutes it was ran. And shows how potential was changing throughout the experiment, the blue graph had a higher temperature change with also changes in the shape. 

This shows an example done in class with only gravitational lines going through the system shown in the image, and as a result we saw that the work was the same for the system because work is path independent  and each path is required from A to C.  

This an example done in class of the voltage potential where there is two point charges among an axis and we were to use the new knowledge we obtained from the prior experiment to see the relationships of the problem and come to a solution of the problem.

This is the other part of the problem in the image before find each part of the problem to find each solution of the problem and found the velocity in the end.

 Next part of the experiment was a demo of a hot dog connected between two charged ends causing it to flow within the hotdog and showing the voltage is moved from one end to the other. Then three LD lights were placed in the hot dog with different distances between their wires, short, medium and a large distance. Knowing what we know from potential we predicted that the one with bigger distance will be brighter because it has a greater voltage potential between the wires. And once the experiment was done we saw that it was correct because of the greater potential between the wires and as shown in the image below will show the set up and light's brightness.

This the lab set up as explained above and the results came out to be that the brightness were determined by the amount of distance each LD light had between their wire leads and prove that the one with the greater distance was the brightest one.

Day 11 Lab 04/07/14

Electric Circuits:

In this lab we were introduced to electric circuits and how each component works from the electric potential to the resistance of materials. We did experiments in which we found different relationships between different variables that give a better understanding why a light bulb lights up when just using a battery and one wire. Also in the lab we were able to see what resistance is and what affects the amount of resistance being applied because certain variables like length for example. Throughout this lab day we saw a circuit can be related to a stream and generator but also the physical definitions of words that we use like voltage and current.

This is the lab set up in which we attempted to light a bub by using the materials in the image and be able to create a close circuit to light it up.

The image shown is what we believe is being traveled through the wire where it is electrons moving from the positive to the negative side of the power supply. However in reality we said that it starts from the negative side and travel through the circuit giving it charge to be able to light the bulb.

After we saw the relationship using another situation we saw that the total power is just multiplying the voltage supplied and the current it gives of as it travels from one point to the other and recycling the electrons.



This another image of the experiment but this time we used equipment that made it easier to make a circuit without using actual hands.

In order to prove the movement inside the current and see the interaction within that wire we needed to place a voltammeter in the circuit to read the amount of amps is in the circuit. After doing the experiment we saw that the current was the same when the voltammeter was moved from one side to the other proving it was the same. We can also use the voltammeter to record the other values in the circuit.

This is the lab setup in which we were able to record the current by placing it in the circuit because it has to be a closed circuit in order to see the current.

The part of the experiment we were given a resistor with a certain amount of coils tied around and we had to use a voltmeter and use it to find the resistance of the resistor. Then we compared values with another group to see the difference in the amount of resistance being applied. In this part of the lab we saw that both of the resistors were close to each other because we had the same amount of coils and similar length of the resistor. However we saw the difference between the other groups and saw there difference of the resistance.

This was the experiment setup in which we were able measure and record the circuit values needed to see the differences when we compared resistors to the other groups. With the voltmeter were able to measure the current, actual voltage and the use calculations to find the resistance.

This is the graph with the values of both groups to compare and see the see the relationship between the voltage and current to see that the relationship is linear  and directly proportional. V=IR.

The second part of the experiment was finding the relationship between the cross sectional area, length, and the material with the resistance. We were given different resistors each with different values in the components stated in the prior sentence and find how each one affects the resistance by using a voltmeter for resistance.

This the values of each resistor with the components stated above to come to a conclusion in the relationships between them and the resistance. At the bottom we can see the relationships of each component for example we saw that the resistance and the length where directly proportional to each other in a linear relationship. In the end came out with an equation incorporating all the values given here.

We used Excel program to make it easier by plugging in all the values and make the calculations less time consuming but the main thing was using the graphs to see the relationships between the cross sectional area, length and material with the resistance and be able to visualize the actual relationship between each one for example like in the image.

Day 10 Lab

Gauss Law

In this part of the lab we saw the charge distribution when its enclosed on a uniform surface and be able to apply Gauss Law to find the values that are needed. After earning flux the day prior the Gauss Law was another way to find the electric field or force of the object. In the lab experiment we did an activity with active physics to see how it interacts and why an conducting sphere has a charge of zero by seeing in Faraday's experiment.

This is  the board where te group wrote the answers to questions in the lab notebook pertaining the Gauss Law and learned the difference between a conducting sphere and insulting sphere or the uniform shape.

This is the Gauss Law for an infinitely long rod where it would be hard to integrate so we replace dQ with lambda to make it easier and find the force to answer the values.

In the end of the lab da we found that the electric force and Gauss Law are the same as the gravitational forces just a different force used. But saw that Earth is a non-conducting sphere and saw the affects it has with certain mass in a different situation seeing that they are related to each other.