AP Physics C: Mechanics 3.1 A Describe the Translational Kinetic Energy of an Object in Terms of the Objects Mass and Velocity Questions

Describe translational kinetic energy as a scalar determined by mass and speed, and apply it to comparisons, multi-object systems, changes in motion, and graphs.

Exam points

calculate translational kinetic energy from an object's mass and speed, independent of direction
compare kinetic energies or required work when mass or initial and final speeds change
sum the translational kinetic energies of multiple objects to obtain a system total
construct or interpret kinetic energy as a function of time from the corresponding speed
relate kinetic energy to momentum or speed while accounting for differences in object mass

[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

AP Physics C: Mechanics 3.1 A Describe the Translational Kinetic Energy of an Object in Terms of the Objects Mass and Velocity Questions question 1