Related AS and A Level Electrical & Thermal Physics essays

1. 

   Determining Avogadro's Number Lab

   4 star(s)

   Thus, the average current after 20 minutes is 0.95 A �10.5%. Time: Time = 60 seconds x 10 minutes Time = 600 seconds Percent uncertainty of time = Percent uncertainty of time � 0.833% The percent uncertainty for time is approximately 0.833%.

2. 

   Measurement of the resistivity of Nichrome

   5 star(s)

   = (Rmin - R) / R Rmin = dmin2�R /d2 Min = (dmin2 /d2) -1 dmin = the mean of d-standard deviation The data in the table below is in 3 decimal place Graph A (Wire A) Graph B (Wire B)

1. 

   Investgating resistivity - Planning and Implementing

   4 star(s)

   The gradient should represent ?/A. Variables The independent variable in the experiment will be the length of constanton wire in the circuit. This variable will be changed, and the dependent variables of voltage and current will be recorded. The resistance in the rest of the circuit will be altered using

2. 

   Finding the Resistivity of a Wire

   However, my graph shows that this was fairly irrelevant, due to the reliability of the line for best fit. o Area of cross-section of wire: I cannot be sure that the wire was cylindrical throughout the wire, which could have affected the resistivity value, though by taking several readings and

1. 

   Characteristics of Ohmic and non-Ohmic Conductors.

   As more electrons flow, current increases. Current (I) Voltage (V) As voltage increases, the temperature increases, the resistance decreases, and hence the graph gets steeper. Resistance (?) Temperature (oC) The resistance of a semiconductor decreases as the temperature increases. I will now experiment to see if my predictions based on my knowledge of the different kinds of conductors are correct.

2. 

   Coulombs Lab Report

   The method we used to charge them, friction by means of a cloth and acetate strip, is almost impossible to measure. Throughout each of the five trials nothing was changed as we simply wanted 5 identical trials.

1. 

   Physics - Resistivity

   Mathematically the temperature dependence of the resistivity '?' of a metal is given by a formula called the Bloch-Gruneissen formula. The Bloch-Gruneissen equation is quite complicated and is as follows. Different materials also affect the resistance of the wire, for example copper is a better conductor than steel, steel is a better conductor than silicon, and so on.

2. 

   Choosing a light source

   So comparing all the readings I obtained with my predication, I can see that my predication was true, the higher the power the less intensity, and the less intensity the higher the brightness. And also the further distance the light source of an object the less brightness observed.