This preview has intentionally blurred sections. Sign up to view the full version.
View Full DocumentThis preview has intentionally blurred sections. Sign up to view the full version.
View Full Document
Unformatted text preview: /35 Spring Quarter 2008 Spring Quarter 2008 Experiment : Coulomb’s Law Your name: Anish Dundoo Partner: Lawrence Powers Performed on: April 17th, 2008 TA: Huard Zach Section number: 249 Promptness % (100 means it was on time): 100 Additional Scores (+)/Penalties (): Please insert your material in the space after the yellow boxes, not in the boxes themselves. Abstract (4) This lab deals with finding the k constant from the force between two electric charges which is calculated using Coulomb’s law. The equation is given by = × × . F k Q1 Q2R2 A torsion balance was used to measure the displacement angle created by getting the two charged spheres to selected distances. The second sphere used the slide assembly for calculating at different distancs. The value of × Q1 Q2R2 was calculated and a graph for force vs. × Q1 Q2R2 was made and the slope estimated the k value. The theoretical value of Coulomb’s constant is , × 8 99mN m2μC2 which compares closely to the experimental value of . × 8 63mN m2μC2 ± . × 31mN m2μC2 . Sample Calculations (5) Calculations for the radius of a sphere, a (m): = am dsphere2 = . ( ) am 3 75 cm 200 = . am 0 01876 Calculations for the geometric factor, (B): =  * B 1 4 a3R2 = a radius of spheres = R distance between the center of the spheres =  *. B 1 4 0188m38 × cm 1m100cm3 = . B 1 0519 =. B 948 Calculations for the corrected angle θ (º): Error: Reference source not found, 09/17/04, Error: Reference source not found = θcorrected θB * = * qM qTR2 μC2m2 qM qTR2 (°)= ° . θcorrected 2 1 000 °= θcorrected 2 Calculations for the X coordinate of the Charge Dependence Graph: * = * *( * ) qM qTR2 μC2m2 VM C VT C R2 * = . qM qTR2 μC2m2 0 50 * . * * . * . * kV 1 92 10 9CkV 2 50kV 1 92 10 * * ( ) . ( ) 9CkV 1 1012 C 0 08 m 2 * = . qM qTR2 μC2m2 0 00072 Calculations for the uncertainty of the X  coordinate of the Charge Dependence Graph: * = ( * )* * *( * ) uqM qTR2 μC2m2 u 1 1012 VM C VT C R2 = Charge CCkV = ( ) Voltage of M VM kV = ( ) Voltage of T VT kV = distance between center of M and T Rcm By Rule 1 from propagation table: = * { } uZ Cu u A ( * )* * *( * ) =( * )* * *( * ) u 1 1012 VM C VT C R2 1 1012 uVM C VT C R2 By Rule 3 from the propagation table (A/B): = * { } + { } uZ Z2 u A A2 u B B2 * * * *( * ) = * * * *( * ) 1 1012 uVM C VT C R2 1 1012 VM C VT C R22 * { * *( * )} * *( * ) + { } u VM C VT C VM C VT C 2 u R2 R22 Page 2 of Word document Error: Reference source not found, 09/17/04, Error: Reference source not found By Rule 3 from the propagation table (A*B): { * *( * )}= * *( * ) * { * } * + {( * )}( * ) u VM C VT C VM C VT C 2 u VM C VM C2 u VT C VT C 2 So by putting that in we get: * = * * * *( * ) uqM qTR2 μC2m2 1 1012 VM C VT C R22...
View
Full
Document
This note was uploaded on 10/12/2009 for the course PHYS physics 21 taught by Professor Larrybortner during the Spring '08 term at University of Cincinnati.
 Spring '08
 larrybortner
 Physics, Power

Click to edit the document details