Tut1 - electric field PDF

Preview

Summary

electric field...

Description

NPHY 172 CHAPTER 21

TUTORIAL 1

13 February 2020

1. How many neutrons does the an atom ฀C have?C have? 2. What is the total charge, in coulombs, of 75kg of electrons? 3. How many electrons would have to be removed from a neutrally charged metal coin to leave it with a net charge of +0.1μC?C? 4. Given two positively charged particles, separated by distance R = 0.02m, with magnitude of charges given as q1=e and q2=2e ( e == elementary charge ). What is the magnitude and direction of electrostatic force on q1 due to q2? 5. What must be a distance between point charge q1=26.0μC?C and point charge q2=47.0μC?C for the electrostatic force between them to have a magnitude of 5.70N? 6. In a return stroke of a typical lightning bolt, a current of about 25000A exists for 20μC?s. How much charge is transferred in this event? 7. Three charged particles, on a Figure on the right, are at the corners of an equilateral triangle. Determine the net electrostatic force on an electron at the centre of a triangle due to all three charges.

8. Two particles are fixed on an x-axis. Particle 1 (q=40μC?C) is located at x=2.0 cm; particle 2 of charge Q is located at x=3.0cm. Particle 3 of charge q=e is released from rest on the y-axis at y=2.0cm. What is the value of Q if the initial acceleration of particle 3 is in the positive direction of (a) the x-axis, with magnitude of 3.5 m/s² and (b) the y-axis, with magnitude of 6.9 m/s²? 9. Explain what does it mean by each of the following: (a) Charge is quantized, (b) Charge is conserved. 10. Give the (a) difference, and (b) similarity between Coulomb’s law and Newton’s law of gravitation.

CHAPTER 22 1. Three point charges are located in a circular arc as shown on the figure on the right. (a) What is the magnitude and direction of the net electric field at P? (b) What will be the magnitude and direction of the net electrostatic force on -5.0nC charge if is placed at P?

2. An electron is released from rest in a uniform electric field of magnitude 100 N/C. Calculate the acceleration of the electron. 3. Explain is details (using diagrams, equations and words) what would happen to an electric dipole if it is placed in a uniform electric field. 4. Given an electric dipole with a dipole moment vector of p = 1.2 nC.m and charge separation of 3.2 μC?m, orientated at an angle of 30° relative to horizontal uniform electric field. Find: (a) Magnitude of each charge, (b) Net torque, (c) Potential energy, and (d) Work done by an electric field, on an electric dipole....