Answer:
A. 
B. 
C. 
Explanation:
The capacitance of a capacitor is its ability to store charges. For parallel-plate capacitors, this ability depends the material between the plates, the common plate area and the plate separation. The relationship is

is the capacitance,
is the common plate area,
is the plate separation and
is the permittivity of the material between the plates.
For air or free space,
is
called the permittivity of free space. In general,
where
is the relative permittivity or dielectric constant of the material between the plates. It is a factor that determines the strength of the material compared to air. In fact, for air or vacuum,
.
The energy stored in a capacitor is the average of the product of its charge and voltage.

Its charge,
, is related to its capacitance by
(this is the electrical definition of capacitance, a ratio of the charge to its voltage; the previous formula is the geometric definition). Substituting this in the formula for
,

A. Substituting for
in
,

B. When the distance is
,


C. When the distance is restored but with a dielectric material of dielectric constant,
, inserted, we have

Answer:
0.429 L of water
Explanation:
First to all, you are not putting the value of the energy given to vaporize water, so, to explain better this problem, I will assume a value of energy that I took in a similar exercise before, which is 970 kJ.
Now, assuming that the water density is 1 g/mL, this is the same as saying that 1 g of water = 1 mL of water
If this is true, then, we can assume that 1 kg of water = 1 L of water.
Knowing this, we have to use the expression to get energy which is:
Q = m * ΔH
Solving for m:
m = Q / ΔH
Now "m" is the mass, but in this case, the mass of water is the same as the volume, so it's not neccesary to do a unit conversion.
Before we begin with the calculation, we need to put the enthalpy of vaporization in the correct units, which would be in grams. To do that, we need the molar mass of water:
MM = 18 g/mol
The enthalpy in mass:
ΔH = 40.7 kJ/mol / 18 g/mol = 2.261 kJ/g
Finally, solving for m:
m = 970 / 2.261 = 429 g
Converting this into volume:
429 g = 429 mL
429 / 1000 = 0.429 L of water
example force. because you can say" I applied 3 newtons downward to the floor".
force has magnitude and direcion
Answer:
D
Explanation:
1.) The reaction is at dynamic equilibrium.
A: Nitrogen and hydrogen combine at the same rate that ammonia breaks down.
2.) Which statement about the reaction is necessarily correct?
A: Both calcium carbonate and sodium carbonate are being produced.
3.) Both calcium carbonate and sodium carbonate are being produced.
A: The reaction is reversible.
4.) What is the fastest motion that can be measured in any frame of reference?
A: 300,000 km/s
5.) Two people are on a train that is moving at 10 m/s north. They are walking 1 m/s south relative to the train. Relative to the ground, their motion is 9 m/s north.
Why are we able to use these motions to describe the motion relative to the ground?
A: The people are moving much slower than the speed of light so the ground acts as a frame of reference.
Answer:
The force of friction acts in opposite direction in which the surface is having tendency to move.
The force of friction is equal to force applied to surfaces, so long as surface is at rest.
Explanation: