A horizontal spring with spring constant 100N/m is compressed 20cm and used to launch a 2.3kg box across a frictionless, horizontal surface. After the box travels some distance, the surface becomes rough. The coefficient of kinetic friction of the box on the surface is 0.15.Use work and energy to find how far the box slides across the rough surface before stopping.

The box slides 0.58 m before stopping .

Explanation:

Given :

Spring constant , k = 100 N/m .

Compression in the spring , x = 20 cm .

Mass of box , m = 2.3 kg .

Coefficient of kinetic friction of the box on the surface is , .

Therefore , conserving energy of the system :

Putting value in above equation we get :

Therefore , the box slides 0.58 m before stopping .

jupiter is the largest planet in our solar system, having a mass and radius that are respectively, 318 and 11.2 times that of earth. suppose that an object falls from rest near the surface of each planet and that the acceleration due to gravity remains constant during the fall. each object falls the same distance before striking the ground. determine the ratio of the time of fall on jupiter to that on earth.