The greatest point for kinetic is at the bottom and in the middle it is in half and at the top it is at the highest in potential energy.
We are given a box that slides up a ramp. To determine the force of friction we will use the following relationship:
Where.
To determine the Normal force we will add the forces in the direction perpendicular to the ramp, we will call this direction the y-direction as shown in the following diagram:
In the diagram we have:
Adding the forces in the y-direction we get:
Since there is no movement in the y-direction the sum of forces must be equal to zero:
Now we solve for the normal force:
To determine the y-component of the weight we will use the trigonometric function cosine:
Now we multiply both sides by "mg":
Now we substitute this value in the expression for the normal force:
Now we substitute this in the expression for the friction force:
Now we substitute the given values:
Solving the operations:
Therefore, the force of friction is 15.01 Newtons.
Answer: E) A) salt water.
Explanation:
E) In equilibrium, pressure exerts equally in all directions, so for a given depth, the pressure is the same for all points located at the same depth, and it can be written as follows:
p = p₀ + ρ.g.h, where p₀ = atmospheric pressure, ρ=fluid density, h=depth from the surface.
A) The buoyant force, as discovered by Archimedes, is an upward force, that opposes to the weight of an object (as it is always downward), and is equal to the weight of the volume of the liquid that the object removes, which means that is proportional to the density of the liquid.
As salt water is denser than fresh water, the buoyant force exerted by the salt water is always greater than the one produced by the fresh water, so objects will float more easily in salt water than in fresh water.
In the limit, it is possible that one object float in salt water and sink in fresh water.
Answer:
F = 1263.03 N
Explanation:s
given,
mass of the disk thrower = 100 Kg
mass of the disk = 2 Kg
angular speed of the disk = 4 rev/s
arm outstretched = 1 m
centripetal force of the disk in the circular path
F = m ω² r
ω = 4 x 2 x π
ω = 25.13 rad/s
F = m ω² r
F = 2 x 25.13² x 1
F = 1263.03 N
hence, centripetal force equal to the F = 1263.03 N
