The frictional force on the crate is given by F = μN where μ = the coefficient of kinetic friction and N = normal force. The normal force equals the weight of the crate W = 180 N.
Since the kinetic friction F = 50 N, and the normal force which is the weight of the crate equals N = W = 180 N, the coefficient of kinetic friction μ is given by μ = F/N
Gravitational potential energy, depends only of the mass on which the gravity is doing work, and the displacement produced by this force.
As displacement depends only on the final and initial positions (in this case, the height of the hill), if we choose as our zero reference level the bottom of the hill, the change in gravitational potential energy will be as follows:
As we can see, the only value of distance involved is the height of the hill , so it is independent of the distance travelled.
<span>When an individual looks through a filtered telescope in which he or she observes the sun, the portion where it appears blotchy is likely to be called the sunspots while the layer of the sun where it shows where it occurs is called the photosphere.</span>
