Blueprint MCAT Formerly Next Step
Return to Blog Homepage

MCAT Physics Question — Frictional Surface

  • by John
  • Sep 04, 2014
  • MCAT Question of the Day

Two people push a box along a frictional surface. One pushes the box at an angle of 30° to horizontal with force F while the other pushes the box horizontally with force Fcos30°. Which person does the most work?

 

frictional surface

 

a) Person A

b) Person B

c) Person A and B do equal amounts of work

d) cannot be determined

 

Explanation

Work is only done by force parallel to the direction of motion per the relationship W=Fdcosθ, and proportional to the distance over which the force is applied. For person A, the vertical component of force F, Fsin30°, does no work since the box moves neither up nor down. Only the horizontal component of the force, Fcos30°, does any work.  For both person A and B, only the force parallel to the motion of the box over the frictional surface does any work. Therefore, the work done by person A and B is equal.

a) Person A, incorrect.

b) Person B, incorrect.

c) Person A and B do equal amounts of work, correct.

d) cannot be determined, incorrect.

Want more MCAT practice?

We’ve got options for every schedule and learning style!

From the best online MCAT course created by top instructors with 524+ MCAT scores to the most representative full-length practice exams and private tutoring, we can custom tailor your MCAT prep to your goals!

Not sure which option is right for you? Schedule a free MCAT consultation with an MCAT expert using the form below. No obligation, just expert advice.

Submit a Comment