1. Resistors
Resistors are the most commonly used component in electronics and their purpose is to create specified values of current and voltage in a circuit. A number of different resistors are shown in the photos. (The resistors are on millimeter paper, with 1cm spacing to give some idea of the dimensions). Photo 1.1a shows some low-power resistors, while photo 1.1b shows some higher-power resistors. Resistors with power dissipation below 5 watt (most commonly used types) are cylindrical in shape, with a wire protruding from each end for connecting to a circuit (photo 1.1-a). Resistors with power dissipation above 5 watt are shown below (photo 1.1-b). |[pic] |[pic] | |Fig. 1.1a: Some low-power resistors |Fig. 1.1b: High-power resistors and rheostats |

as the temperature increase, the resistance tends to increase. However, there are two types to this: Ohmic and non-Ohmic
Ohmic resistor's resistance increase with temp linearly whereas non-Ohmic would have a curve(e-function)

Look at related question below for a full explanation on color banded resistors including temperature drift.

The effect of temperature on resistance of a given material depends on the material. In conductors, an increase in temperature will result in an increase in the resistance. In semiconductor materials, increasing temperature will result in a decrease in resistance.

...WRITING RESEARCH REPORTS
The following set of guidelines provides psychology students at Essex with the basic information
for structuring and formatting reports of research in psychology. During your time here this will be
an invaluable reference. You are encouraged to refer to this document each time you write a labreport.
The writing of laboratory reports is an essential part of any practical module in Psychology. This is
because psychologists (and more generally most scientists) write accounts of their studies using a
standard format, which makes explicit certain aspects of the study. There are two main reasons for
doing this:
(1) Ease of communication: it is easier to find what you want from a study if it
is written in the standard format.
(2) Provision of a precise and complete description: the format makes it clear what
information is important for scientific communication. This information must be provided
in detail. It should be added that many professions now include the skills of technical report
writing, which requires clear, direct and concise
expression, the ability to summarize and present data, and the ability to form
hypotheses and draw valid inferences. Learning to write laboratory reports will provide you
with a valuable and transferable skill.
This guide tells you about the structure and style that is required for a psychology laboratory...

...
PhysicsLabReport
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...

...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,...

...
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...

...
Lab 3. Dc circuits and Ohm’s law of measurments
Helina Wolfe
Tannaz Farnoudi and Najah Rouse
Physics 246-205
Professor Joe Renaud
09/23/13
Word count:1453
Abstract:
The aim of this experiment was to understand the relationship between the variables of Ohm’s law and how they are part of an operation of an electric circuit.
Introduction:
This experiment was done in two parts. The first part consisted of understanding how to determine the current, voltage and resistance as part of Ohm’s law. The second part consisted of how to use the variables in an electrical current. Knowing how the variables are used in calculations and electrical currents is important in determining the value of the resistor and how it affects the current in the circuit. A device known as the multimeter is used to find the voltage and current in the circuit. Ohm's principal discovery was that the amount of electric current through a metal conductor in a circuit is directly proportional to the voltage impressed across it, for any given temperature. Ohm expressed his discovery in the form of a simple equation, describing how voltage, current, and resistance interrelate:
V= IR equation (1)
This continuous movement of free electrons through the conductors of a circuit is called a current (I). Current is often referred to in terms of “flow. The force motivating electrons to "flow" in a circuit is called voltage, which is a specific measure of...

...
“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...

...
Centro de investigación y desarrollo de educación bilingüe (CIDEB)
PhysicsLABREPORT
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...

...needle on a pool of liquid, a gradient to the earth’s magnetic field would not be detected. The needle will not drift, but will just rotate. For this experiment, we can assume that the earth’s magnetic field is uniform at one spot on earth. There is a vertical and horizontal component to the earth’s magnetic field. At the north pole end, the compass would point down into the earth. Around 35% of the total magnetic field is horizontal (parallel to the earth’s surface) at our latitude.
For this lab, a vector calculation is used to prove that the magnetic field produced by a current in a wire is directly proportional to the current in the wire. We also demonstrate that the number of loops is directly proportional to the field inside a series of the loops. From these results the fields from the geometry and the current can be calculated. Using Ampere’s law, the strength of the Earth’s magnetic field and can be calculated to then be compared to literature values.
Purpose: The purpose of this lab is to calculate of the magnetic field of a current loop and measuring the Earth’s magnetic field by comparing it to literature values.
Loops
Loops
The object of the experiments is to investigate some of the parameters that affect the magnetic field inside a loop of wire (BL).
Power Supply
Power Supply
Ammeter
Ammeter
Procedure:
Make sure that you have an integer set of loop in your apparatus. Starting with 5 loops. We set up a system so...