Problem 1
A body of mass m starts from rest on a frictionless track and descends a vertical height H, then moves onto a rough horizontal surface with kinetic-friction coefficient μ. The horizontal surface is long enough for the body to stop; take g=9.8 m/s² and neglect other resistance. (a) Find the speed on reaching the horizontal using mechanical-energy conservation. (b) Find friction and acceleration on the horizontal. (c) Determine stopping distance s using kinematics and confirm by work–energy. Use SI units throughout and treat components as ideal exactly as specified. State sign conventions when writing equations and retain units in final results.
problems.proof.stepOf
problems.proof.analysis
Insert the intermediate result into the relevant definition or equation to obtain the final expression. Checking signs and limits catches a wrong branch or omitted constraint.