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:
Because of inertia (Newton's First Law of motion)
Explanation:
According to Newton's First Law of motion:
"An object at rest (or in motion at constant velocity) will tend to stay at rest (or tend to keep moving with same velocity) unless acted upon an unbalanced force"
In this problem, the object we are analyzing is the coffee cup.
At the beginning, the cup is at rest, together with the car.
Later, the car starts moving when the light turns green.
If we apply Newton's First Law of motion to the cup, we see that the coffee cup tends to keep its state of rest: for this reason, as the car moves forward, the coffee in the cup will spill backward, into the rear seat. This property of an object to mantain its state of motion is also called as inertia.
There are several possibilities. Here are a few that occur to me:
-- If Point-A is the summit of Pike's Peak, he may feel somewhat
short of breath.
-- If Point-A is his grandmother's house, he may feel a great sense
of pleasant anticipation.
-- If Point-A is his office on Monday morning, then he may feel
a tightening sensation in his chest.;
-- If Point-A is his home on Friday afternoon, then he feels the
effects of a slow and steady drop in his blood pressure.
I finer point might be put to it if we had any idea of where
Point-A is, and what it represents in the grand scheme
of things.
Answer:
The work done on the Frisbee is 1.36 J.
Explanation:
Given that,
Mass of Frisbee, m = 115 g = 0.115 kg
Initial speed of Frisbee, u = 12 m/s at a point 1 m above the ground
Final speed of Frisbee , v = 10.9674 m/s when it has reached a height of 2.00 m. Let W is the work done on the Frisbee by its weight. According to work energy theorem, the work done is equal to the change in its kinetic energy. So,
So, the work done on the Frisbee is 1.36 J. Hence, this is the required solution.
