Answer:
The correct answer is 
Explanation:
The formula for the electron drift speed is given as follows,
where n is the number of of electrons per unit m³, q is the charge on an electron and A is the cross-sectional area of the copper wire and I is the current. We see that we already have A , q and I. The only thing left to calculate is the electron density n that is the number of electrons per unit volume.
Using the information provided in the question we can see that the number of moles of copper atoms in a cm³ of volume of the conductor is 
. Converting this number to m³ using very elementary unit conversion we get 
. If we multiply this number by the Avagardo number which is the number of atoms per mol of any gas , we get the number of atoms per m³ which in this case is equal to the number of electron per m³ because one electron per atom of copper contribute to the current. So we get,
if we convert the area from mm³ to m³ we get 
.So now that we have n, we plug in all the values of A ,I ,q and n into the main equation to obtain,
which is our final answer.
Answer:
A. The brakes used a coil system to convert the kinetic energy into potential energy stored in the brakes
Explanation:
Based on the law of conservation of energy, the brakes used a coil system to convert the kinetic energy into potential energy stored in the brakes.
The law of conservation of energy states that energy is neither created nor destroyed in a system but it is transformed from one form to another.
As the airplane slows down, the kinetic energy which is presented in the motion of the plane is gradually converted to potential energy.
The potential energy is the energy due to the position of a body.
Do you have any options? My guess would be distance but I could be wrong.
Answer:
Pressure,P=6×10^3Pa
Explanation:
The gas has an ideal gas behaviour and ideal gas equation
PV=NKT
T= V/N p/K ...eq1
Average transitional kinetic energy Ktr=1.8×10-23J
Ktr=3/2KT
T=2/3Ktr/K....eq2
Equating eq1 and 2
V/N p/K = 2/3Ktr/K
Cancelling K on both sides
P= 2/3N/V( Ktr)
Substituting the value of N/V and dividing by 10^-6 to convert cm^3 to m^3
P = 2/3 (5.0×10^20)/10^-6 × 1.8×10^-23
P= 6 ×10^3Pa
