Question

A block sliding with velocity v>0 along a frictionless floor hits a spring at time t=0 (configuration 1). The spring compresses until the block comes to a momentary stop (configuration 2). (Figure 1) Finally, the spring expands, pushing the block back in the direction from which it came. In this problem you will be shown a series of plots related to the motion of the block and spring, and you will be asked to identify what the plots represent. In each plot, the point labeled "1" refers to configuration 1 (when the block first comes in contact with the spring). The point labeled "2" refers to configuration 2 (when the block comes to rest with the spring compressed). In the questions that follow, "force" refers to the xcomponent of the force that the spring exerts on the block and "position" and "velocity" refer to the xcomponents of the position and velocity of the block. For all graphs, treat the origin as (0,0); that is, the x axis represents y=0 and the y axis represents x=0.

Part A Consider graph A. What might this graph represent?   position vs. time   velocity vs. time   force vs. time   force vs. position Part B Consider graph B. What might this graph represent?   position vs. time   velocity vs. time   force vs. time   force vs. position

Part C

Consider graph C.

What might this graph represent?

	position vs. time
	velocity vs. time
	force vs. time
	force vs. position

Answer 1

A) position vs. time

at t = 0, x = 0

and t = T/4 x, = A

B) force vs. position

at x = 0, F = 0

and F = -k*x

it looks like y = m*x

C) velocity vs. time

at t = 0, v = vmax

at t = T/4, v = 0