Two rocks have equal mass Two rocks have equal mass. Which has more gravitational potential energy? QuickCheck 25.1 Rock A Rock B They have the same potential energy. Both have zero potential energy. 2

Two rocks have equal mass Two rocks have equal mass. Which has more gravitational potential energy? QuickCheck 25.1 Rock A Rock B They have the same potential energy. Both have zero potential energy. Increasing PE 3

QuickCheck 25.2 Two positive charges are equal. Which has more electric potential energy? Charge A Charge B They have the same potential energy. Both have zero potential energy. 4

QuickCheck 25.2 Two positive charges are equal. Which has more electric potential energy? Charge A Charge B They have the same potential energy. Both have zero potential energy. Increasing PE 5

QuickCheck 25.3 Two negative charges are equal. Which has more electric potential energy? Charge A Charge B They have the same potential energy. Both have zero potential energy. 6

QuickCheck 25.3 Two negative charges are equal. Which has more electric potential energy? Increasing PE for negative charge Charge A Charge B They have the same potential energy. Both have zero potential energy. 7

QuickCheck 25.4 A positive charge moves as shown. Its kinetic energy Increases. Remains constant. Decreases. 8

QuickCheck 25.4 A positive charge moves as shown. Its kinetic energy Increases. Remains constant. Decreases. Increasing PE Decreasing KE 9

QuickCheck 25.5 A positive and a negative charge are released from rest in vacuum. They move toward each other. As they do, A positive potential energy becomes more positive. A positive potential energy becomes less positive. A negative potential energy becomes more negative. A negative potential energy becomes less negative. A positive potential energy becomes a negative potential energy. 10

QuickCheck 25.5 A positive and a negative charge are released from rest in vacuum. They move toward each other. As they do, A positive potential energy becomes more positive. A positive potential energy becomes less positive. A negative potential energy becomes more negative. A negative potential energy becomes less negative. A positive potential energy becomes a negative potential energy. 11

QuickCheck 25.6 A proton is released from rest at the dot. Afterward, the proton Remains at the dot. Moves upward with steady speed. Moves upward with an increasing speed. Moves downward with a steady speed. Moves downward with an increasing speed. 12

QuickCheck 25.6 A proton is released from rest at the dot. Afterward, the proton Remains at the dot. Moves upward with steady speed. Moves upward with an increasing speed. Moves downward with a steady speed. Moves downward with an increasing speed. Decreasing PE Increasing KE 13

QuickCheck 25.7 If a positive charge is released from rest, it moves in the direction of A stronger electric field. A weaker electric field. Higher electric potential. Lower electric potential. Both B and D. 14

QuickCheck 25.7 If a positive charge is released from rest, it moves in the direction of A stronger electric field. A weaker electric field. Higher electric potential. Lower electric potential. Both B and D. 15

QuickCheck 25.8 Two protons, one after the other, are launched from point 1 with the same speed. They follow the two trajectories shown. The protons’ speeds at points 2 and 3 are related by v2 > v3 v2 = v3 v2 < v3 Not enough information to compare their speeds. 16

QuickCheck 25.8 Two protons, one after the other, are launched from point 1 with the same speed. They follow the two trajectories shown. The protons’ speeds at points 2 and 3 are related by v2 > v3 v2 = v3 v2 < v3 Not enough information to compare their speeds. Energy conservation 17

QuickCheck 25.9 What is the ratio VB/VA of the electric potentials at the two points? 9 3 1/3 1/9 Undefined without knowing the charge 18

QuickCheck 25.9 What is the ratio VB/VA of the electric potentials at the two points? 9 3 1/3 1/9 Undefined without knowing the charge Potential of a point charge decreases inversely with distance. 19

QuickCheck 25.10 An electron follows the trajectory shown from i to f. At point f, vf > vi vf = vi vf < vi Not enough information to compare the speeds at these points. 20

QuickCheck 25.10 An electron follows the trajectory shown from i to f. At point f, vf > vi vf = vi vf < vi Not enough information to compare the speeds at these points. Increasing PE (becoming less negative) so decreasing KE 21

QuickCheck 25.11 At the midpoint between these two equal but opposite charges, E = 0; V = 0 E = 0; V > 0 E = 0; V < 0 E points right; V = 0 E points left; V = 0 22

QuickCheck 25.11 At the midpoint between these two equal but opposite charges, E = 0; V = 0 E = 0; V > 0 E = 0; V < 0 E points right; V = 0 E points left; V = 0 23

QuickCheck 25.12 At which point or points is the electric potential zero? A. B. C. D. E. More than one of these. 24

QuickCheck 25.12 At which point or points is the electric potential zero? V = 0 V = 0 A. B. C. D. E. More than one of these. 25