Two bodies, A and B, collide as shown in Figures I and II below. Which statement is true?
A)They exert equal and opposite forces on each other in I but not in II.
B)They exert equal and opposite force on each other in II but not in I.
C)They exert equal and opposite force on each other in both I and II.
D)The forces are equal and opposite to each other in I, but only the components of the forces parallel to the velocities are equal in II.
E)The forces are equal and opposite in I, but only the components of the forces perpendicular to the velocities are equal in II

Question

Two bodies, A and B, collide as shown in Figures I and II below.  Which statement is true?
A)They exert equal and opposite forces on each other in I but not in II. 
B)They exert equal and opposite force on each other in II but not in I. 
C)They exert equal and opposite force on each other in both I and II. 
D)The forces are equal and opposite to each other in I, but only the components of the forces parallel to the velocities are equal in II. 
E)The forces are equal and opposite in I, but only the components of the forces perpendicular to the velocities are equal in II

Quizplus · Accepted Answer

According to Newton's Third Law of motion, for every action, there is an equal and opposite reaction. This means that the forces exerted by A and B on each other are always equal and opposite in magnitude and direction. This is true for both cases shown in Figures I and II, so the correct choice is C.

Two Bodies, a and B, Collide as Shown in Figures