Question

Which of the following best describe about the statement " A block moves up and down on a spring. The magnitude of the force of the spring on the block is directly proportional to the distance the spring is stretched ".

• A. Inertia
• B. Unbalanced forces
• C. Action and reaction force pairs
• D. Universal gravitation
• E. Simple harmonic motion

Answer 1

Answer: (E)

Simple harmonic motion

For a spring- block system the restoring force is $F=-ky$,

or, $F\propto -y$ where k is spring constant and $y$ is vertical displacement (stretch) of spring from mean position ,

we can see that magnitude of force is directly proportional to the distance the spring is stretched that is the necessary condition for SHM, therefore it is a SHM.