Introduction
Dielectric materials are insulators that make it harder for the electric field to penetrate the space within a capacitor; this is due to the theory of polarization. In Lab 4 (Parallel Plate Capacitor), the objective was to measure the dielectric constant (κ) of a textbook (paper) using a makeshift capacitor of aluminum foil. This was done through graphical analysis by the linearization of equation (1). The goal was to construct a linear graph in which the slope and slope error was calculated using the Linest function, the slope than allows for the derivation of the dielectric constant of the paper in a textbook. Error propagation (error formulas) was also used in this lab to account for sources of errors that could have occurred.
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In this equation C is the capacitance of the capacitor, κ is the dielectric constant of the insulating material, ε0 is the permittivity of free space, A is the area of the charged plate, and d is the dielectric thickness. This equation was rearranged to C = κε0A(1/d) as a linear line of y = mx + b, in which C = y, 1/d = x, and κε0A = slope(m).
(2) F = x/y = lFl x ((δx/IxI) + (δy/lyl)) was used for the error propagation of 1/d where x = 1 and y = d. This equation was also used for the error propagation of κ = slope/ ε0A where x = slope and y = A.
(3) F = xy = lFl x ((δx/IxI) + (δy/lyl)) = xδy + yδx was used for the error propagation of area where length = x and width = y to get the area of the parallel
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This suggests error in experimental procedure. Possible explanations for this error would be that air which has a dielectric constant of κ ≈ 1 still exists within the aluminum parallel plates; this will affect the calculations of κ to be a lower value such as the one in this experiment. Another explanation would be the difficulty in very small measurements. This experiment required the measurement of capacitance values around 10-12, and values this small show great error in precision, also the measurements of the page thickness and area of the parallel plate were very small. Also, he make-shift aluminum parallel plate capacitor is a lower quality instrument (non-professional) being used. This being said, paper is not a very good material for a commercial capacitor because it has a low dielectric constant. The dielectric constant of paper is still higher than air which means it is better than just air but it is small compared to other dielectrics with a higher dielectric constant. Larger dielectric constants are better because C ∝ κ as seen in equation (1), this means that the larger the dielectric constant, the greater stored charge for a given voltage because C = Q/V. Larger dielectric constants also prevent the conducting plates from coming into direct electrical contact. If the plates are not aligned properly, the area in calculations can only be the
Ewald Georg von Kleist is a German scientist who created the capacitor in November of 1745. Regrettably, Kleist did not have the proper paper work to claim in the records that the design of the capacitor was his idea. Many months later, a Dutch professor named Pieter van Musschenbroek created the Leyden jar, the world’s first capacitor (on record). It was a simple jar that was half filled with water and metal above it. A metal wire was connected to it and that wire released charges. Benjamin Franklin created his own version of the Leyden jar, the flat capacitor. This was the same experiment for the more part, but it had a flat piece of glass inside of the jar. Michael Faraday was the first scientist to apply this concept to transport electric power over a large distance. Faraday created the unit of measurement for a capacitor, called Farad.
Experimental: The experimental procedure outlined in the OU Physical Chemistry Laboratory Manual was followed without any deviations.
This function will replace the f by the tangent that was estimate by pn value. The function finds the upper and the lower limit and interpolates where the point in between will fall. The root of the equation will be given by this number. Figure 6 shows how the interpolation of the middle value is found by means of the tangent line. The tangent line, in red, is fixed at a point and uses the upper and lower limits to find a single iteration.
had an absolute error in the slope of only 0.0007 s/°C and the absolute error in the intercept of
The magnitude which depict the capability of dielectric material to retain the electric charge when it exposed to an electric field.[54] when two metal sheet is subject to electric field, one of these sheet will be negative, and the other will be positive, in this case, the dielectric material in the space between these two sheet will polarize, the dielectric constant is then represent as the ratio electric charge stored by dielectric material to that when the dielectric material is
Studies have shown that big changes in temperature do not affect the capability of insulation. In one experiment, materials were set to a high heat of 300 degrees Celsius. After six months in this environment, the substances were cooled to room temperature. The dielectric constant showing the level of insulation had not changed ("Teflon PTFE fluoropolymer resin" 28).
In the experiment these materials were used in the following ways. A piece of Veneer wood was used as the surface to pull the object over. Placed on top of this was a rectangular wood block weighing 0.148-kg (1.45 N/ 9.80 m/s/s). A string was attached to the wood block and then a loop was made at the end of the string so a Newton scale could be attached to determine the force. The block was placed on the Veneer and drug for about 0.6 m at a constant speed to determine the force needed to pull the block at a constant speed. The force was read off of the Newton scale, this was difficult because the scale was in motion pulling the object. To increase the mass weights were placed on the top of the ...
Change of Color and Gaseous release was observed in (B1, B2, B3, B4 ) each had cloudiness, and a change in compression. In B1 the bubbling became gradual and eventually turned the Aluminum shot red in color. B2 had a series of bubbling through the experiment, eventually eroding the Aluminum foil. B3 trial was very responsive to the Copper chloride and the Zinc became Black. B4, Ammonium hydroxide had a thick level of blue above the remaining clear
Polman, H., Orobio De Castro, B. & Van Aken, M. A.G. (2008). Experimental Study of the
The historical results of this experiment by determination of the charge to mass ratio of an electron allowed physicist to work out the miniscule mass of an electron through the use of an external magnetic field. Magnetic fields apply a magnetic force on charged particles perpendicular to their direction of motion and to the magnetic field itself. This allows for the magnetic force to act as a centripetal force which then, through analysis, allows for the determination of certain charged particles through the analysis of their curve radius. In lab 15, Measurement of Charge to Mass Ratio for Electrons, the objective was to measure the charge to mass ratio (e/m) of an electron through the use of a mercury vapor chamber. This was done through the graphical analysis by the linearized equation (4). The goal was to construct a linear graph in which the slope and slope error was calculated using the Linest function, the slope than allows for the derivation of the charge to mass ratio of an electron. Error propagation (error formulas) was also used in this experiment to account for sources of error that could have occurred.
In doing this, let us consider that freely falling objects moves in a vertical direction that is, along the y-axis. instead of using Δx, we will use Δy.
A capacitor is a device for electrical charge. A simple capacitor is two plates made of an electrically conducting material separated by a non-conducting material or dielectric. A capacitor can come in a huge variety of sizes and types for use in regulating power as well as for conditioning, smoothing and isolating signals. Almost every electrical and electronic system uses them. [1]
...inty between 1.0% (0.1/10.00*100) and 2.13% in the measured volume and 0.1/4.70*100). We also used a digital thermometer that allowed us to read the temperature readings from five degrees celcius to eighty degrees celcius. Since the digital thermometer have an absolute accuracy of plus or minus one degree celcius, it gives a percent uncertainty between 0.125 % (0.1 / 5.00 * 100) and 0.2 % (0.1/ 80.0 * 100). One of the difficulties we faced during the lab is reading the inverted graduated cylinder. To account for the inverse meniscus, we subtracted 0.2 mL from all the volumetric measurements to account for that. Volumetric uncertainty is the most important in determining the accuracy of this experiment since we are constantly checking for the volume throughout the lab. It also is the factor that gives the highest percent uncertainty out of all the instruments used.
whereβ the intercept 0 and β the slope 1 are unknown constants and ε is a random error component .
Dielectrics and dielectric properties are defined generally and dielectric measurement methods and equipment are described for various