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) The temperature will be ~4000K which would be about 3276 degrees Celcius. 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) The temperature would be about 7050 degrees Celcius.

b) Light bulbs operate at 2500 degrees C.
What is the wavelength at which the most power is emitted for a light bulb operating at 2500 C? The wavelength would be equal to 1000nm
ii) Explain why regular incandescent bulbs waste a lot of energy. Be sure to include your reasoning. The majority of the light emitted is at wavelengths that are longer than that, that are visible. So the power going into the light bulb that is producing non-visible light is wasted. It is wasting energy that way, so regular incandescent bulbs are inefficient.

2) In this problem we will explore the greenhouse effect by using the Greenhouse Effect Simulation available from http://phet.colorado.edu/simulations/sims.php?sim=The_Greenhouse_Effect
a) Explore the simulation.
True or False

The only effect of increasing the number of clouds...

...Name ___Anjad Itayem_______________ Blackbody RadiationLab 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...

...
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...

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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...

...trials were performed or if the class data were to be compared and averaged. Performing the experiments under a vacuum and frictionless setting would remove external variables that affect the data leading to more precise numbers. More accurate percent discrepancies illustrating laws of conservation can be achieved by adding more trials and including more sophisticated measuring tools. These techniques would lead to more accurate results to reduce any experimental errors and to better validate the concepts of energy and momentum conservation.
Conclusion
The purpose of the experiment was to investigate simple elastic and inelastic collisions to study the conservation of momentum and energy concepts. The objective of the lab was met since the validity of the Law of Conservation of Momentum was confirmed by determining the relationship of energy and momentum conservation between inelastic and elastic collisions by utilizing percent discrepancy calculations. The calculations state that the percent discrepancies for inelastic collisions were 8.75% and 19.23 % for the equal mass and unequal mass respectively. The percent discrepancies for the equal and unequal mass elastic collisions were 22.07% and 9.78 % respectively. Both of the percent discrepancies for the elastic collisions were close to the 10%-15% range which validates the concept of momentum conservation in inelastic elastic collisions. In regards to conservation of energy,...

... 9/16/14
Physics 01L
Density
Abstract
This experiment was conducted in order to determine the density of the Aluminum metal samples provided in the lab. Specific tools such as the vernier caliper and balance scale were used to measure and record the values found. Given that density is a measurement of mass over volume, both of these quantities would have to be determined experimentally, prior to proceeding with the calculation of the density, for each of the six subjects tested. Being as accurate and precise as possible, the data yielded a density that was similar to that of the accepted value for the density of aluminum. Taking averages of the measurements recorded by both partners may have introduced a variable for error. However, upon calculating the percent error of the results found, it was concluded that there was less than a three percent error, which supported the accuracy and credibility of the experiment.
Data
Table 1: Tabular Presentation
Aluminum
Diameter D1 (cm)
Diameter
D2 (cm)
Average
Diameter (cm)
Height
H1 (cm)
Height
H2 (cm)
Average Height (cm)
Mass (g)
Volume
(cm3)
1
1.27 cm
1.27 cm
1.27 cm
1.55 cm
1.548 cm
1.549 cm
5.6 g
V=1.96cm3
2
1.26 cm
1.266 cm
1.263 cm
2.64 cm
2.64 cm
2.64 cm
9.6 g
V=3.31 cm3
3
1.26 cm
1.266 cm
1.263 cm
4.726 cm
4.728 cm
4.727 cm
16.6 g
V=5.92 cm3
4
1.26 cm
1.268 cm
1.264 cm
6.218 cm
6.216 cm
6.217 cm
21.8 g
V=7.80 cm3
5...

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Experiment 7: Relative Density
Laboratory Report
Marella Dela Cruz, Janrho Dellosa, Arran Enriquez,
Alyssa Estrella, Zacharie Fuentes
Department of Math and Physics
College of Science, University of Santo Tomas
España, Manila Philippines
Abstract
The experiment was conducted to show the different methods on how to determine an object’s composition through its density and to determine an object’s density by displacement method and the Archimedes Principle. Results show that. The materials used were the spring scale, beaker, 25 pieces of new 25 centavo coins, a bone from a pig’s leg, diet and regular soft drinks, and a pycnometer.
1. Introduction
Density is a physical property of matter. It is the mass per unit volume of a substance. In this experiment, relative density is also used to be able to determine the composition of the substances or objects used. Relative density is the ratio of a density of a substance to that of the density of a given reference material. It is also known as specific gravity. Density is used when making or building objects that are required to float such as ships on water and airplanes in the sky.
Objectives:
1. To determine the density of an object by displacement method
2. To determine the composition of a substance based on its density
3. To determine the density of a substance by Archimedes Principle
2. Theory
Relative Density (R.D.) or also known as Specific gravity (S.G.), is the raito of the density of...

...Conduction, Convection, and Radiation
The three types of heat transfers are Conduction, Convection, and Radiation. Heat always moves from a warmer place to a cooler place. For example hot objects that are in a room that is cooler than the temperature of the object will eventually cool to room temperature. First is conduction, conduction is heat transferring through direct contact of substances. Then convection, which is the transfer of heat by the movement of the warmed matter. Lastly radiation is electromagnetic waves that directly transport heat through space.
Conduction is the transfer of heat between substances that are in direct contact with each other. The better the conductor is the faster the heat will transfer. The best conductor of heat is a metal. Conduction occurs when a substance is heated and when particles gain energy they start to vibrate more. Then the particles will bump into nearby particles and transfer some of their energy them. This process continues and passes the energy from the hot end down to the colder end of the substance.
Convection occurs when warmer areas of a liquid or gas rise to cooler areas in the liquid or gas. Cooler liquid or gas will take the place of the warmer areas which have risen higher. This ends up in a circulation pattern that keeps going. A good example of convection is water boiling in a pan of the convection currents. Another example of convection occurs...

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“The Domino Effect”
Teacher’s Prompt
Investigate the domino effect with a set of dominoes.
Aim
To investigate the relationship between the mass of the dominoes, and how it impacts the time taken of the domino effect.
Independent Variable: The mass of each domino (12.38 g, 32.38 g, 42.38 g, 62.38 g, 82.38 g).
Dependent Variable: Time taken of the domino effect.
Controlled Variable: The number of dominoes used (8 dominoes), the distance between the dominoes (2 cm), the loads used as the initial force applied on the domino (50g), the inclined plane used as a platform that will direct the load to hit the first domino (20o), the stopwatch used to time the domino effect, the person using the stopwatch, the person releasing the metal weight from the top of the inclined plane, the ruler used to measure the distance between the dominoes.
Equipment
1 Inclined Plane
1 (50 g) Metal Weight
4 x 8 (20 g) Metal Weight
8 Dominoes (Uno Stackos)
1 Digital Mass Balance (± 0.01 g)
1 Masking Tape
1 Protractor
1 Ruler
1 Stopwatch (± 0.01 s)
-34290039687500Diagram
Analysis of Variables
Independent Variable:
The mass of the dominoes will vary ranging from 12.38 g to 82.38 g. The increase between each of the variable will be constantly 20 g, to satisfy the range of the mass; the original mass of the domino is 12.38 g, and an additional mass from a 20 g of load will be attached on top of the domino for every change in variable.
Dependent Variable:
In accordance to...