Solutions5

# A 4pt you push a block of mass across a table at

This preview shows page 1. Sign up to view the full content.

This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: [4pt] You push a block of mass across a table at speed while applying a constant power . After you stop pushing, the block slides a distance before coming to rest. Which of the following is a correct expression for the power ? Sorry, the correct answer was omitted from the choices, but that means everyone gets credit. If you have to push with power to keep the block moving, then friction is applying power – to the box. When you stop pushing, only the frictional power is still applied to the box, so , using the work-energy theorem and the definition of power. Since the box decelerates at a constant rate, w he r e is the velocity while it was being pushed. Thus, and (b) [4pt] The potential energy of an object as a function of position is , where is measured in Joules and is measured in meters. Where would the object be located if it was in stable equilibrium? m m The equilibrium position is where Setting gives m m with so the answer is C. Note: the equilibrium position is not where . The definition of potential energy is always arbitrary up to an additive constant, so no physical meaning can be attributed to one particular value. Only difference...
View Full Document

## This document was uploaded on 03/09/2014 for the course PHYS 221 at Ohio Northern University.

Ask a homework question - tutors are online