AP Physics C: Mechanics 3.1 Translational Kinetic Energy Questions

Analyse translational kinetic energy as a mass- and speed-dependent scalar for individual objects and systems, including comparisons, changes, graphs, and momentum links.

Exam points

calculate and compare translational kinetic energy using its quadratic dependence on speed
combine individual kinetic energies or connect kinetic energy with momentum for a system
interpret work requirements or kinetic-energy graphs when an object's motion changes

Covered syllabus points

3.1.A—Describe the translational kinetic energy of an object in terms of the object’s mass and velocity

[Maximum number: 1]

Mech.2.
A block of mass 2 M rests on a horizontal, frictionless table and is attached to a relaxed spring, as shown in the figure above. The spring is nonlinear and exerts a force $F(x)=-B x^{3}$ , where B is a positive constant and x is the displacement from equilibrium for the spring. A block of mass 3 M and initial speed $v_{0}$ is moving to the left as shown.

Determine an expression for the kinetic energy of the two-block system immediately after the collision.

1 point
Using a proper expression for kinetic energy of the two-block system

\begin{aligned} K & =\frac{1}{2} m v^{2} \\ K & =\frac{1}{2}(5 M)\left(\frac{3}{5} v_{0}\right)^{2} \end{aligned}

For an answer consistent with part (b)

K=\frac{9}{10} M v_{0}^{2}

All question bank results loaded

Covered syllabus points

Question 1