Two - Tone Siren

A.

B.

- Electronic PNP Transistor: a semiconductor device use to amplify and switch electronic signals and power

- 22K Ohm Resistor: resistors reduce current flow and act to lower voltage levels within circuits 

- 0.022 uF Ceramic Capacitor: a polarized capacitor which user an electrolyte to achieve a large capacitance 

- 0.1 uF Ceramic Capacitor: a fixed value capacitor that is constructed of layers of ceramic and metal material acting as an electrode (flow of electrons) 

- 0.047 uF Ceramic Capacitor: a fixed value capacitor that is constructed of layers of ceramic and metal material acting as an electrode (flow of electrons) 

C. How It Works:

The resistors and multiple capacitors in the circuit control the flow of the current throughout. The PNP transistor controls the direction of the flow in the circuit. The board mainly utilizes V1, V2, and V3 in order to use the corresponding batteries in the set. In the circuit, some wires connect the board to the speaker in order to hear the sound of the siren. Other wires connect to the side switches, which controls the tone of the siren itself. We did not have any wires connecting to the main switch. The remaining wires connect to the Power Trans for the circuit. 

D. In this circuit, we had very little difficulty. We were surprised to find out that the directions from the Level 1 book is missing wires to the on-offswitch (or maybe we missed them), so we decided not to connect it. At one point, we had all wires and pieces connected, but had no sound. We reviewed wire connections and capacitor placement. We discovered that our 0.047 Ceramic Capacitor was in the wrong slots, and once adjusted, we still had no sound. Our problem was solved by switching the PNP transistor around so that each wire was in its correct position. We continued to remove and add this piece when turning the sound on and off since we decided not to connect the switch, which shows us how the flow of current works throughout our circuit. 

E. Our video: https://m.youtube.com/watch?v=wliCcOBHeAw

Photos:

Fish Caller

A. 

                   

                      

     

B. In this circuit, we utilized a(n)...

- Electronic PNP Transistor: a semiconductor device use to amplify and switch electronic signals and power

- 4.7K Ohm Resistor: resistors reduce current flow and act to lower voltage levels within circuits 

- 3.3 uF Electrolytic Capacitor: a polarized capacitor which user an electrolyte to achieve a large capacitance 

- 0.1 uF Ceramic Capacitor: a fixed value capacitor that is constructed of layers of ceramic and metal material acting as an electrode (flow of electrons) 

C. How It Works:

In this circuit, we have a resistor to control the current flow. In this board, we are mainly utilizing the first, second, and third battery, as seen by the origin of the wires. We have wires connecting to the Power Trans for the circuit. We have wires connecting to the switch, which turns the sound on and off, and connecting to the frequency and volume, which we used to adjust the fish caller sound. The PNP Transistor directs the flow of current within our circuit. 

D. In this circuit, we were far more prepared, but still encountered difficulty. After connecting the resistors, transistors, and capacitors, we moved on to connecting the wires to the appropriate places. Once we finished and hit the switch, there was no sound. Our first mistake was missing the wire connected to spring terminal 68, which we fixed and still had no sound. Mr. E went through each piece with us, checking that we had each resistors and capacitor correct. 

     In the end, it turns out that the Electronic PNP Transistor was backwards. In this process, we retrained to the front of the book for directions to find which wire was E, C, and B. Once in place, our sound was working and we used to frequency switch to change the sound and tone of the caller. I'm pretty sure we heard some fish rustling in the lake!

E.

 

Our Video: https://m.youtube.com/watch?v=KKPhfinN2tg

Photos:

               

      

Light Sensitive Bird

 

A.

 

B. In this circuit, we utilized a(n)...

- Electronic PNP Transistor: a semiconductor device use to amplify and switch electronic signals and power

- 10K Ohm Resistor: resistors reduce current flow and act to lower voltage levels within circuits 

- 1k Ohm Resistor: resistors reduce current flow and act to lower voltage levels within circuits 

- 0.047 uF Ceramic Capacitor: a fixed value capacitor that is constructed of layers of ceramic and metal material acting as an electrode (flow of electrons) 

- 100 uF Electrolytic Capacitor: a polarized capacitor which user an electrolyte to achieve a large capacitance 

- 0.1 uF Cermaic Capacitor: a fixed value capacitor that is constructed of layers of ceramic and metal material acting as an electrode (flow of electrons) 

- LED: (Light Emitting Diode) is a one-way path for electricity, or current flow 

C. How It Works:

In this circuit, we have resistors throughout to control the flow of the current. In the main board, each column under V1, V2, V3, and so on connects to the corresponding battery shown in the photos. We have wires connecting to the Power Trans. Other wires connect to the speaker from the board in order for us to hear the sound of our bird. Other wires connect to the switch from the board in order to turn the bird sounds on and off. Wires also connect to the frequency and volume buttons. Most important, we have wires connecting our board and diode in order to use the light sensitive function of the project. 

D.      Considering this was our first circuit project, we had some misunderstandings in placement and directions in the beginning. When it came to the resistors and capacitors, our first mistake was with the Electrolytic Capacitor in determining which side was the positive end. As a result, we were required to return to the beginning of the Level 1 book to check. We performed this same process with the PNP Transistors in determining which wire was E, B, or C. 

     After dealing with the individual pieces, we moved on to the wires (which we didn't quite know how to connect in the first place. Mr. E was helpful enough to provide us some guidance and actually place the wire within the spring terminal, and not just simply on top). After finishing the twelve connections, we hit the switch and!!!...nothing. We checked our smaller individual pieces, our batteries, our switch. We eventually realized that we were missing the wire connections between our Power Trans and Speaker. Once we fixed this, we hit our switch and successfully made our Light-Sensitive Chirp! We adjusted the frequency, the volume, and the amount of light that was allowed to go through the diode. 

E.

Our Video: https://m.youtube.com/watch?v=jTd7968jaIg

Photos: 

Resistors in Series and Parallels, not feelin' creative today

Objectives:

- To study current flow in series and parallels

- To study voltages in series and parallels

- Use Ohm's law to calculate equivalent resistance of series and parallels

Key Terms:

- voltage

- circuit

- electricity

- series

- parallels

Pre-Lab Discussion :

What do Series Resistors look like? What do Parallel Resistors look like? What is the difference between the two?

Resistors in series come in succession of each other. In parallel resistors, the resistors split on their owns paths and provide separate "roads"

What is Ohm's Law? 

Ohm's Law states that the current through a conductor between two points is directly proportional to the potential difference across the two points. Introducing the constant of proportionality, the following mathematical equation can be used to describe the relationship:

Our Setup ft. The Physics Students:

Procedure and Data:

Resistor One: 1.08V/0.055A = 19.6, close to the actual resistance of 20 (Two 10 Ohm resistors)
Resistor Two: 1.12V/0.018A = 62.2, close to the actual resistance of 61 (Two Resistors: 51 and 10)
Resistor Three: 1.05V/0.0104A = 100.96, close to the actual resistance of 102 (Two 51 Ohm resistors)

Resistors 51 and 51: 1/51 + 1/51 = 2/51 or 51/2 * 0.0404 = 1.03 V, or the voltage recorded

Resistors 51 and 68: 1/51 + 1/68 = 68/3468 + 51/368 = 119/3468 or 3468/119 * 0.035 = 1.02 V, or about the voltage recorded

Resistors 68 and 68: 1/68 + 1/68 or 68/2 = 34 * 0.031 = 1.054 V, or about the voltage recorded

In the following section, we compared a parallel circuit with 10 and 51 Ohm Resistors as well as 51 and 68 Ohm Resistors. In this experiment, we expected the experiment to begin, and with a different current going through each resistor. 

The ratio of the currents (A1/A2) should equal (R1/R2)
In this photo, we can see a different current going through each resistor, proving that the current will split between the two resistors.  The split is clearly not equal. 

      In this photo, we also see the current splitting between the 10 and 51 Ohm resistors. The split is clearly not equal. 

Analysis:

1. Describe Resistors in Series and Parallel 

In Series circuits, there is only one pathway for the flow of electrons. The current running through each resistor is equal, and the net change of energy is 0. The more resistors in a series, the lower the overall current of the system. In order for series to work, all resistors must be functioning. 

In Parallel circuits, the current has multiple pathways available to cross. The current running through is split to the resistors, and not necessarily evenly. As the number of resistors increases, the overall current increases. Unlike series, parallel circuits are able to function with one resistor gone, but not as efficiently as before.  

2. Describe the flow of the current in resistors in series? 

We proved that the flow of current in resistors in series is equal. 

3. Describe the flow of the current in resistors in parallel? 

We proved that the flow current in resistors is split between the pathways and the different flows of current are not necessarily equal.

4. Which resistor had the larger current flowing through it? 

In our experiment with the two set of parallel resistors, we found that the resistor with the highest value of resistance had the highest value of current flowing through it. We assume this is due to a higher resistance, or a higher tolerance for the current. Otherwise, the resistor overflows and overheats and starts to smoke as you yell "MAXIMUM VOLTAGE" and your teacher looks on with disapproval wondering how his brilliant physics students managed to destroy a 10 Ohm resistor with only 3 volts. 

Ohm's Law Lab

What was the name of the first electricity detective? Sherlock Ohms

Objectives: 

• Determine the mathematical relationship between current, potential difference, and resistance in a simple current
• Compare the potential difference vs. current behavior of a resistor to that of a light bulb

Key Terms:

• current
• potential difference
• resistance
• circuit
• voltage
• electric potential

Pre-Lab Discussion: What is Ohm's Law?

Ohm's Law states that the current through a conductor between two points is directly proportional to the potential difference across the two points. Introducing the constant of proportionality, the following mathematical equation can be used to describe the relationship:

Materials: 

• Vernier Circuit Board
• wires and clips
• two resistors (10 and 50)
• light bulb (6.3 V)
• Vernier Current and Voltage Probe

Lab Setup: 

Procedure:

1. Resistor One (10Ω) - The power supply was connected and data was kept at every 0.5 V

     At event number five, our Current (A) is 0.2063 and our Potential (V) is 2.023. When we divide our voltage by our current, we get a resistance of about 9.806, which is close to the actual resistance of 10 

Ω

2. Resistor Two (50Ω) - The power supply was connected and data was kept at every 0.5 V

    At event number two, our Current (A) is 0.0326 and our Potential (V) is 1.665. When we divide our voltage by our current, we get a resistance of about 51.07, which is close to the actual resistance of 50 

Ω

3. Lightbulb (6.3 V) - The power supply was connected and data was kept at every 0.5 V (versus every 0.1 V) 

   Based upon this data, we can assume that the resistance of the lightbulb is about 36.58 Ω

Analysis:

In this lab, we are trying to prove the relationship of R = V/I, V standing for voltage, I for current, and R or resistance. Graphs one and two, which display potential voltage on the y-axis and current on the x-axis, proves the two are proportional. The slopes of the graphs, which are nearly identical to the resistance of each resistor, prove the proportional relationship between the two. The data of both Graph one and two is in a straight line that passes through zero, proving the proportional relationship between the current and voltage. 

We know that the resistors follow Ohm's Law because the relationship between I, V, and R is followed between two points and the voltage divided by the current is equal to the resistance.

For the section of the lab that involved the lightbulb, the change was linear. Based upon the slope of the graph, we believe the light bulb has a resistance of about 36.58 Ω. As the voltage increased, the current remained with it in a proportional relationship, following Ohm's Law. 

Rolling Rally?!?!?!

Objectives:

1. Come up with a list of measurable physical characteristics that may affect the outcome of a "race" and create a hypothesis for how each might affect the result.

2. Design a series of experiments that will allow you to test your hypotheses.

3. Synthesize your results to create a model that will allow you to predict the winner of a race between two rolling objects.

4. Explain how your results relate to the Law of Conservation of Energy.

Key terms:

- energy

- velocity

- speed

- hypothesis 

- conservation 

- radius

- mass

Pre-Lab Discussion and Explanation: In this lab, we are trying to relate the different conditions of our lab to the Law of Conservation of energy. The law, which involves kinetic and potential energy, states that the energy of a system cannot be created nor destroyed, but simply transformed. In this lab, the controls in our experiment are two balls with the same diameter, mass, and distribution of mass. 

Let's Get Right to it - The Races:

Race 1: Different Masses

- 24 g ball vs. 94.9 g ball

- Same radius 

- Same distribution of mass

- Hypothesis: The mass of the balls will not affect the speed 

In this experiment, we proved that a difference in mass does not affect the race. Both balls reach the bottom of the ramp at the same time. 

Race 2: Distribution of Mass

- Mass doesn't matter (proven earlier) 

- Hypothesis: a different distribution of mass WILL affect speed

Race 3: Different Diameters 

- Mass does not matter (proven earlier)

- Hypothesis: The radius of the balls WILL affect the speed, meaning one will go faster

Analysis:

Question: How does this relate to the Law of Conservation of Energy? Did we break the law? Are we going to physics jail?

Answer: First off - no, we didn't break the Law of Conservation of Energy, and no, we aren't going to jail. The Law of Conservation of Energy involves gravitational potential energy (m*g*h) and kinetic energy (1/2*m*v^2). 

In the lab, we had potential energy converting into kinetic energy. The kinetic energy will be in two forms: translational (1/2*m*v^2) and rotational kinetic energy (1/2*I*w^2). If an object has a larger translational kinetic energy, it will have a small rotational energy. For example, a solid disk has a smaller rotational energy.

An equal distribution of mass and an object with greater diameter travel as a greater speed than their opposing object. In our lab, we believe that the increase in speed is due to a greater moment inertia, or I, relating to the torque of the object. To photos below will be able to explain and walk through the translation: 

Centripetal Force Lab CHALLENGE GET PUMPED

Objectives:

• to relate centripetal acceleration and Newton's second law: F = ma

Key Terms:

• velocity
• radius
• acceleration
• force
• mass
• average

Pre-Lab Discussion:

This lab connects Newton's second law, (F=ma), to centripetal acceleration, which is a relationship of the tangential velocity squared divided by the radius (a = V^2 / r ). In order to prove this relationship, we needed to measure force, velocity, mass, and radius. The rest of the this lab shows how we did this:

Our Setup and Materials:

• force probe
• Photogate
• ball
• string
• base and stand

Trial One Graph:

Radius: 0.495 meters

Trial Two Graph:

Radius: 0.35 meters


Analysis:

T R I A L  O N E 
Mass: 0.66  gram
Force: (see graphs - averaged force) 0.7463
a = Fm (F = ma)
 0.7463 = 0.66a
a = 11.30  m/s^2 (tangential)

or

Mass: 0.66 grams
Velocity: (see graphs - averaged velocity) 0.6387 m/s
Radius:  m
a = V^2/r
a = (0.6387^2)/(0.495)
a =  0.761 m/s^2 (centripetal)


T R I A L  T W O
Mass: 0.66 gram
Force: (see graphs - averaged force) 0.7488 N
a = Fm (F = ma)
0.7488 = 0.66a
a = 11.35 m/s^2 (tangential)

or

Mass: 0.66 grams
Velocity: (see graphs - averaged velocity) 0.5162 m/s
Radius: 0.35 m
a = V^2/r
a = (0.5162^2)/(0.35)
a = 0.824 m/s^2 (centripetal)

Overall Idea:

f=ma is used to find tangential velocity, whereas a = V^2/r is for finding the centripetal acceleration. In our lab, we expected to calculate the force, velocity, time, and acceleration of the system. We expected the acceleration of F = ma to equal the a of a = V^2/r, but, based on our results, that is not what was calculated.