Engineering Physics
posted by Christine .
A 4kg box is compress 50 cm on a spring (k=100 N/m) and then slides across a horizontal floor. If (u=0.4) between the box and the floor
1) How much work is done by friction as the box comes to a stop?
2) Assuming the frictional force is constant, how far will the box slide before it comes to a stop?

1) The work done by friction will equal the initial potential energy of compression in the spring, but will be of the opposite sign. Work is done against friction, not by it.
2)
(1/2)kd^2 = M*g*u*X
d is the initial spring compression.
g is the acceleration of gravity
M is the box's mass
k is the spring constant
u is the kinetic coefficient of friction
Solve for X, the distance that the box slides.
Respond to this Question
Similar Questions

physics
A box which has a mass of 48 kg is dragged across the floor a distance of 5.9 m. If the coefficient of friction between the box and floor is 0.53, how much nonconservative work is done by friction? 
physics
1. A student is dragging a 5 kg box along the floor. He pulls on the rope with a 25 Newton force. The rope is 37 degrees above horizontal. As the box slides 10 meters, it goes from a speed of 3 m/s to a speed of 7 m/s. a.) calculate … 
Physics help!
A box of books weighing 323 N is shoved across the floor by a force of 477 N exerted downward at an angle of 35° below the horizontal. (a) If μk between the box and the floor is 0.51, how long does it take to move the box 4.80 … 
Physics (work and springs)
A 4kg box is compressed 50cm on a spring (k=800 N/m) and then slides across a horizontal floor. If (u=0.4) between the box and the floor... A) how much work is done? 
physics
A box of books weighing 314 N is shoved across the floor by a force of 475 N exerted downward at an angle of 35° below the horizontal. (a) If μk between the box and the floor is 0.53, how long does it take to move the box 5.00 … 
PHYSICS
A 5.00kg box slides 7.00 m across the floor before coming to rest. What is the coefficient of kinetic friction between the floor and the box if the box had an initial speed of 3.00 m/s? 
physics
a 20kg box sits on a level floor. the coefficient of kinetic friction between floor and box is 0,60. how large a friction force opposes the motion of the box while moving? 
Physics
A box of books weighing 337 N is shoved across the floor by a force of 467 N exerted downward at an angle of 35° below the horizontal. (a) If μk between the box and the floor is 0.56, how long does it take to move the box 4.00 … 
Physics
A box of books weighing 337 N is shoved across the floor by a force of 467 N exerted downward at an angle of 35° below the horizontal. (a) If μk between the box and the floor is 0.56, how long does it take to move the box 4.00 … 
physics
A force of 55 N at an angle of 32 degrees to the horizontal is applied to drag a 15kg box across a horizontal floor at a velocity of 2.5 m/s. The coefficient of friction between the box and the floor is 0.25 and the box is moved 15m …