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PHY 2049: Physics II. Tutoring Center is open in room NPB 1215, M-F 12:00AM -4:00PM. It is free. Hopefully all homework problems have been solved. Please see me immediately after the class if there is still an issue. PHY 2049: Physics II.
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PHY 2049: Physics II • Tutoring Center is open in room NPB 1215, M-F 12:00AM -4:00PM. It is free. • Hopefully all homework problems have been solved. Please see me immediately after the class if there is still an issue.
PHY 2049: Physics II • About bicycle riding: If some one shows you a trick, it means that, • It is possible to do that trick • The person who showed you, can do the trick. • It does not mean that you can do the trick. • Try it a lot of times and you can too.
PHY 2049: Physics II What have we learned • Coulomb’s law, electric field, Gauss’ theorem and electric potential. • All comes together in the concept of a capacitor. Capacitor: A device to store charge.
PHY 2049: Physics II • Calculate the Electric Field at P • Calculate the el. potential at P
PHY 2049: Physics II • Point charge • Distribution of charges • Line charge at an edge • Disc on an axis through the center
PHY 2049: Class Quiz If 500 J of work are required to carry a charged particle between two points with a potential difference of 20V, the magnitude of the charge on the particle is: A. 0:040C B. 12:5C C. 20C D. cannot be computed unless the path is given E. none of these
Some old business: What is the electric field of a shell of a uniform spherical charge distribution? What is the potential for each of the above?
PHY 2049: Physics II • Some old business The potential of a uniform spherical charge. • Calculate electric field, integrate it to get the potential E r R V V
Two particles with charges Q and -Q are fixed at the vertices of an equilateral triangle with sides of length a. The work required to move a particle with charge q from the other vertex to the center of the line joining the fixed particles is: A. 0 B. kQq/a C. kQq/a2 D. 2kQq/a E. 1.4kQq/a
PHY 2049: Physics II • a= 39 cm • q1 = 3.4pC • q2 = 6 pC • E at the center? • What is the potential at the center?
PHY 2049: Physics II • Capacitors: A device to hold charge. • It is held by Coulomb force between the charges. +q and –q on two separate places. • V : potential difference: q= CV • C: capacitance units farad.
