Students who do well in quantitative problem solving have difficulties with purely conceptal problems.

Give your students the following questions, on successive days. The questions address the same issue in physics, but one provides them an easier opportunity to just plug-n-chug.

Two blocks, one with a mass of 1 kg the other with a mass of 2 kg, start from rest. They experience a constant force of 10 N for 1 s. What are their kinetic energies after the force has been applied.  

Correct Answer

Two blocks, one with twice the mass of the other, start from rest. They experience the same constant force for 1 s. Compare their kinetic energies after the force has been applied.

 Correct Answer

Students that have this difficulty will tend to solve the first problem with little or no hardship, but be unable to answer the second.

 

Related misconceptions/student difficulties that may arise in the question:

 Students use compensation arguments to incorrectly solve conceptual problems.