The graph in the figure shows the force on an object as a function of the elongation caused by that force.Which statement about this object is true?
A)The object obeys Hooke's law at all points from A to C.
B)The object obeys Hooke's law at all points from B to C.
C)The object obeys Hooke's law at all points from A to B.
D)The elastic limit occurs at point C.
E)The region of elastic behavior occurs from B to C.

Question

The graph in the figure shows the force on an object as a function of the elongation caused by that force.Which statement about this object is true? 
A)The object obeys Hooke's law at all points from A to C. 
B)The object obeys Hooke's law at all points from B to C. 
C)The object obeys Hooke's law at all points from A to B. 
D)The elastic limit occurs at point C. 
E)The region of elastic behavior occurs from B to C.

Quizplus · Accepted Answer

Hooke's law states that the force applied on a spring is directly proportional to the amount of deformation produced in the spring. In other words, the force versus elongation graph for a spring obeying Hooke's law should be a straight line passing through the origin. From the given graph, we can see that the object obeys Hooke's law only from point A to point B since the graph is a straight line in this region. Beyond point B, the graph starts to curve, indicating that the object is no longer obeying Hooke's law. Therefore, option C is the correct choice.

The Graph in the Figure Shows the Force on an Object