An 52.0 N box of clothes is pulled 7.3 m up a 30.0° ramp by a force of 103 N that points along the ramp. If the coefficient of kinetic friction between the box and the ramp is 0.22, calculate the change in the box's kinetic energy.
workin=frictionwork+changePE+changeKE
103N*7.3m=mu(mg)cos30*7.3+mg*7.3*sin30+KEchange
solve for KE change
I got 571, but it says it's wrong!!
Nevermind!! I got it! Thank you so much
To calculate the change in the box's kinetic energy, we need to find the work done on the box. The work done on an object is equal to the force applied multiplied by the distance over which the force is applied. In this case, the force applied is the component of the force parallel to the ramp, and the distance is the displacement of the box up the ramp.
First, let's find the component of the applied force parallel to the ramp. We can find this by multiplying the applied force by the cosine of the angle between the applied force and the ramp.
Parallel component of the force = Applied force * cos(angle)
Parallel component of the force = 103 N * cos(30.0°)
Next, let's find the work done on the box by multiplying the parallel component of the force by the displacement along the ramp.
Work = Parallel component of the force * displacement
Work = (103 N * cos(30.0°)) * 7.3 m
Now, we need to find the work done against friction. The work done against friction is equal to the frictional force multiplied by the displacement.
Frictional force = coefficient of kinetic friction * normal force
The normal force is equal to the weight of the box, which is given as 52.0 N. Therefore,
Frictional force = 0.22 * 52.0 N
Finally, the work done against friction is:
Work against friction = Frictional force * displacement
Work against friction = (0.22 * 52.0 N) * 7.3 m
The total work done on the box can be found by subtracting the work done against friction from the work done by the applied force:
Total work = Work - Work against friction
Now, we can calculate the change in kinetic energy using the work-energy principle. The change in kinetic energy is equal to the total work done on the box.
Change in kinetic energy = Total work
Calculate the value of Total work using the formulas above, and you will find the change in the box's kinetic energy.