AP® Physics C: Mechanics 2023 Scoring Guidelines
© 2023 College Board
Question 1: Free-Response Question 15 points
For correctly drawing and labeling the force of gravity and the normal force on both dots
For drawing and labeling the spring force to the left on both dots, where the force for
Spring Q (Trial 2) is twice as long as the force for Spring P (Trial 1)
Example Solution
Scoring Note:
Examples of appropriate labels for the force due to gravity include:
,
,
,
,
,
, “grav force”, “F Earth on block”, “F on block by Earth”,
,
. The labels
and
are not appropriate labels for the force due to gravity.
,
,
, “normal force”, “ground force”, or similar labels may be used for the
Scoring Note: A response that includes extraneous vectors can earn a maximum of 1 point.
For a statement that the work is equal to the area under the curve
For stating the spring compression will be greater than
with an attempt at a relevant
justification
For a justification that indicates that the heights are equal when the area between each
function and the horizontal axis
are equal, which happens after x = 0.040 m
Scoring Note: While a mathematical solution is not required to earn credit for this point,
students may reference a mathematical solution.
Example Solution
The work don
e by each spring is equal to the area under their respective curves. This work is
converted to the change in potential energy and therefore relates to the maximum height
reached by the block. At
, the area under the curve for Spring Q is greater than
Therefore, it is not until a compression greater than
that the
areas under the two curves are
equal, have the same work, and convert to the same
