Problem 3P

Exploring Energy Concepts

An object whose weight is 100 lbf experiences a decrease in kinetic energy of 500 ft · lbf and an increase in potential energy of 1500 ft · lbf. The initial velocity and elevation of the object, each relative to the surface of the earth, are 40 ft/s and 30 ft, respectively. If g = 32.2 ft/s2, determine

(a) the final velocity, in ft/s.

(b) the final elevation, in ft.

Solution

Step 1 of 3

Consider an object whose weight is which experience a decrease in kinetic energy and an increase in potential energy of .

We need to find out the final velocity and the final elevation in if the initial velocity relative to the surface of the earth of the object is and the initial elevation relative to the surface of the earth of the object is .