Materials: Styrofoam cupsStyrofoam platesPVC Pipe
FurScotch Tape
Procedures:
You will be investigating charging object by friction. When you are asked to write your observations, please do so in a clear, complete manner.

1. Tape a piece of string to a Styrofoam cup and hang it from the edge of the desk so that it can move freely. Rub the outside of the cup with fur. Rub a PVC pipe with fur and bring it near the hanging cup. A. Observations: Cup is repelled

B. How does the distance between the PVC Pipe and the cup affect the results you observe? The closer the objects are, the more the cup is repelled.
2. Take the PVC pipe and rub it with fur. Bring the fur near the suspended cup. A. Observations: Cup is attracted.
B. What might you conclude with your observations?
The cup and the fur have opposite charges.
3. The forces between charged objects are called electric forces. When a charged object is brought close to the hanging cup, the cup is acted on by three forces: gravitational force pulling down, the string tension pulling up along the string, and the electric force. A. Can you keep the hanging cup in a stable position with a single charged cup or PVC? B. Can you keep the hanging cup in a stable position with two or more objects? C. Sketch force diagrams showing all of the forces acting on the hanging cup for at least two different situations.

4. Hang two cups next to each other and see what happens?
Repel each other.
5. Bring the PVC pipe near the hairs on your arm. What happens? The hairs stand up.
6. Charge two plates with fur. Try floating one on top of another. Can this work? Why or why not? Explain. The top plate floats a little bit; the weight of the plate is too much for the electrostatic force. 7. Take approximately 15 cm of scotch tape and hang it from the desk so that it isn’t clinging to anything and it is free to swing. Rub the PVC Pipe with fur...

...ELECTROSTATICS - I – Electrostatic Force
1. Frictional Electricity 2. Properties of Electric Charges 3. Coulomb’s Law 4. Coulomb’s Law in Vector Form 5. Units of Charge 6. Relative Permittivity or Dielectric Constant 7. Continuous Charge Distribution i) Linear Charge Density ii) Surface Charge Density iii) Volume Charge Density
Frictional Electricity:
Frictional electricity is the electricity produced by rubbing two suitable bodies and transfer of electrons from one body to other.
+ ++
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Glass Silk
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- - - -
.- - Ebonite Flannel
Electrons in glass are loosely bound in it than the electrons in silk. So, when glass and silk are rubbed together, the comparatively loosely bound electrons from glass get transferred to silk. As a result, glass becomes positively charged and silk becomes negatively charged. Electrons in fur are loosely bound in it than the electrons in ebonite. So, when ebonite and fur are rubbed together, the comparatively loosely bound electrons from fur get transferred to ebonite. As a result, ebonite becomes negatively charged and fur becomes positively charged.
It is very important to note that the electrification of the body (whether positive or negative) is due to transfer of electrons from one body to another. i.e. If the electrons are transferred from a body, then the deficiency of electrons makes the body positive. If the electrons are gained by a body, then the...

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Centro de investigación y desarrollo de educación bilingüe (CIDEB)
PhysicsLAB REPORT
Uniform Rectilinear Motion
Teacher: Patrick Morris
Alejandra Castillejos Longoria
Group: 205
ID: 1663878
Abstract
The purpose of this experiment, was to prove the concept of the uniform linear motion by using an air track. With this, we demonstrated the impulse and change in momentum, the conservation of energy and the linear motion. We basically learnt to calculate the distance/time, acceleration/time, and velocity/time and graph it. The air track is also used to study collisions, both elastic and inelastic. Since there is very little energy lost through friction it is easy to demonstrate how momentum is conserved before and after a collision. According to the result, the velocity of the object in the air track was constant, it means that it didn’t have acceleration because it has constant velocity.
Introduction
First of all; we should understand what is linear motion. Linear motion is motion along a straight line, and can therefore be described mathematically using only one spatial dimension. Uniform linear motion with constant velocity or zero acceleration. The Air Track can be used to obtain an accurate investigation of the laws of motion. A car or glider travels on a cushion of air provided which reduces friction. Since the friction is all but removed the car will be moving at...

...Saif Ismail Pendulum
Go to http://phet.colorado.edu/simulations/sims.php?sim=Pendulum_Lab
and click on Run Now.
1. Research to find equations that would help you find g using a pendulum. Design an experiment and test your design using Moon and Jupiter. Write your procedure in a paragraph that another student could use to verify your results. Show your data, graphs, and calculations that support your strategy.
Procedure:
The equation used to calculate the period of oscillation of single pendulum is T = 2π * sqrt( L / g). From that, we can calculate “g” through the equation, g = (4π^2 * L) / T^2. In these equations, T is the period of oscillation, L is the length of the pendulum, and g is the constant of the acceleration from gravity. To calculate an accurate value for g, I used 2 values for L on Moon and Jupiter of 2.5m and 1.00m. From there I used the simulation to calculate T and I plugged that into the equation to find g. The average value of g on the moon is 1.606m/s^2. Also, the average value of g on Jupiter is 18.913m/s^2. The results are listed in the table below.
Location
Length(m)
Period(s)
Acceleration of Gravity(m/s^2)
Moon
2.50m
9.022s
1.213m/s^2
Moon
1.00m
5.736s
1.999m/s^2
Jupiter
2.50m
2.264s
19.255m/s^2
Jupiter
1.00m
1.458s
18.571m/s^2
2. Use your procedure to find g on Planet X. Show your data, graphs, and calculations that support your conclusion.
Location
Length(m)
Period(s)
Acceleration of Gravity(m/s^2)...

...ElectrostaticLab
What materials will you use?
I will use the virtual lab and elements provided by the class
What would you measure?
I will measure the static electricity with a neutrally charged balloon
What results do you expect?
I expect that the balloons charges and sticks to the wall.
What is the result are different?
That would mean that there is a different way to charge the balloons than negative charge as using your hair.
EXPERIMENT
Bring together the balloons but not touching each other.
Rub a balloon in sweater.
Rub several times the balloon and the sweater so there is more attraction
Bring the balloon as close to the wall as possible but without touching.
OBSERVATION
They kept the same, so they couldn’t be charged.
The balloons sticks to the sweater because it was attracted to the sweater and charged.
There is a greater exchange of electrons so the balloon get more charge and sticks more to the sweater.
Nothing happened, objects kept the same
Experiment
Rub the uncharged balloon with the wall
The balloon is more attracted to the sweater that to the wall
Rub both balloons together
Observation
The balloon kept the same, it wasn’t charged.
The sweater became proton charged, this means that the balloon will be more attracted to the sweater than to the wall.
Objects kept the same because non of them was charged.
After touching the blue balloon with the sweater,...

...Name ___Anjad Itayem_______________ Blackbody Radiation Lab 11
Go to http://phet.colorado.edu/simulations/sims.php?sim=Blackbody_Spectrum
and click on Run Now.
1) In this lab, you will use the Blackbody Spectrum Simulation to investigate how the spectrum of electromagnetic radiation emitted by objects is affected by the object's temperature. In this simulation, you can input the temperature and observe the spectrum of the radiation emitted.
a) The temperature of stars in the universe varies with the type of star and the age of the star among other things. By looking at the shape of the spectrum of light emitted by a star, we can tell something about its average surface temperature.
i) If we observe a star's spectrum and find that the peak power occurs at the border between red and infrared light, what is the approximate surface temperature of the star? (in degrees C)
Using the Spectrum Simulator, I found that this border is in the neighborhood of 4045 Kelvin, which converts to approximately 3772o C
ii) If we observe a stars spectrum and find that the peak power occurs at the border between blue and ultraviolet light, what is the surface temperature of the star? (in degrees C)
Using the Spectrum Simulator, I found that this border is in the neighborhood of 7080 Kelvin, which converts to approximately 6807o C
b) Light bulbs operate at 2500 degrees C.
i) What is the wavelength at which the most power is...

...ElectrostaticsElectrostatics is a part of physics is that the study and analysis of electricity, its properties and its applications. Electrostatics was discovered when an ancient Greek philosopher named Thales. In 600 B.C., Thales learned that when he rubbed amber with fur, it would start to attract other lightweight objects such as feathers and dust which is now known as a process called triboelectrification. This is also how we got the word electricity, which comes from the Greek word, elektron, which means amber. Thales, who is now known as one of the Seven Wise Men, is believed to be the first person to ever experiment with electrostatics. After the death of Thales, no further experiments were conducted dealing with electrostatics until the 17th century when a man by the name of William Gilbert continued Thales’s research. He studied magnetism and static electricity. Gilbert repeated the experiment by Thales with rubbing and charging objects using friction. He later invented the word “electric” to label the forces at work for whenever an object repelled or attracted the other one. He discovered that when objects rubbed, the act removed a fluid (humour) from one of the objects and it also left an atmosphere (effluvium) around the object.
The thought that electricity could also exist as a fluid continued throughout the 18th century. In 1729, there was an English scientist named...

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PhysicsLab Report
How does the length of a string holding a pendulum affect its oscillation?
Method
1. You will need the following apparatus: a pendulum, a piece of string, a clamp, a clamp stand and a timer.
2. Measure out 20cm and attach the metal ball.
3. Establish an angle and let the ball swing for 10 oscillations, timing it and stopping at the 10th one.
4. Write down your results.
5. Repeat steps 2-4 another 2 times so that your results are reliable.
6. Then change the length of the string 4 times, so that you get 5 different sets of results and for each time, repeat it 3 times.
DCP
Raw Data
Data Processing
Calculations:
To find the average of the time, I added all 3 values and then divided by three. For example:
(0.89+0.83+0.89)/3 = 0.87
I calculated the absolute uncertainty by considering the furthest point from the mean. For example:
1.31 (mean) – 1.25 (furthest point from the mean) = 0.06
Therefore my absolute uncertainty is +/- 0.06
I calculated the percentage uncertainty by dividing the absolute uncertainty by the mean and multiplying it by 100, like this:
(0.03/1.70) x100 = 0.18%
Source of uncertainties:
The uncertainties in the measurement came primarily from the equipment. Since we used a ruler that was divided into parts of 0.1cm, the readings were normally rounded up or down. The length of string was constant in all 3 times that we...