Multiple Choice (1 pt each) Instructions: Clearly circle one correct answer for
ID: 2040531 • Letter: M
Question
Multiple Choice (1 pt each) Instructions: Clearly circle one correct answer for each question 35 1. Electriç potential is Force per unit charge ) Potential energy per unit charge C) Force per unit distance D) Electric field per unit charge E) Electric field per unit distance Two charges, +q and -q, are held in place a distance d from each other. What is true about the total electric potential energy of the charges? 2. A) U is negative U is positive C) U is zero D) U is sometimes positive, sometimes negative E) There is no potential energy, all energy is kinetic energy Three identical charges, with charge +q, are held in place at the corners of an equilateral triangle with side length d (see image to the right). How will the electric potential energy change if one of charges is replaced with a charge of -q 3. +q A) U will increase B) U will decrease U will not change U will become 0 +q tq E) U cannot be determined for combinations of positive and negative charges. 4. An electron is placed in the electric field between two parallel conducting plates. What direction will the electron move? A) In the direction of increasing potential B) In the direction of decreasing potential C) Perpendicular to the electric field. D) In the same direction as a proton placed between the conducting plates E) The electron is in equilibrium and will not move. Page 1 of 8Explanation / Answer
1) B) potential energy per unit charge
2) A) U is negative
U = k*q1*q2/d
= k*(q)*(-q)/d
= -k*q^2/d
3) B) U will decrease
because, Ui = k*q^2/d + k*q^2/d + k*q^2/d
= 3*k*q^2/d
Uf = -k*q^2/d - k*q^2/d + k*q^2/d
= -k*q^2/d
4) A) in the direction of increasing potential.
electron attacts towards positive plate and moves towards positive plate.
so, electron moves towards increasing potential.
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.