Follow along with the video below to see how to install our site as a web app on your home screen.
Note: This feature may not be available in some browsers.
Bring your 2026 application questions to our open office hours with Emil Chuck, PhD, Director of Advising Services for HPSA, and get them answered live. Personal statements, secondaries, interview prep, school list strategy. Sunday, May 17 at 9 p.m. Eastern.
For this question, how do we know to use 1000N and not 5000N? both are decelerating forces...and the 5000N specifically corresponds to the 40 m/s the question is referring to. Help please??
The question starts out by saying, "If no braking occurs". Therefore, the generator was not engaged (no 5000 N at 40 m/s was engaged) and no stationary surface was added to the wheels to decelerate. If no braking occurs, then we have no deceleration (constant velocity of 40 m/s). So we must look at the free body diagram: 1000 N of force due to rolling friction/internal friction must be balanced by the power needed to maintain constant velocity. So the power output must be 1000 N x 40 m/s.