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: 2.83 J/mol
Explanation:
Heat of solution, sometimes interchangeably called enthalpy of solution, is said to be the energy released or absorbed when the solute dissolves in the solvent. A solute is that which can dissolve in a solvent, to form a solution
Given
No of moles of CaCl = 7.5 mol
Total energy used = 21.2 J
Heat of solution = q/n where
q = total energy
n = number of moles
Heat of solution = 21.2 / 7.5
Heat of solution = 2.83 J/mol
Answer:
Explanation:
Given: The latent heat of fusion for Aluminum is 
mass to be malted m = 0.75 Kg
Energy require to melt E = mL
Therefore, energy required to melt 0.75 Kg aluminum
Explanation:
Given that,
Initial speed of the bus, u = 0
Acceleration of the bus, a = 0.5 m/s²
Let v is the velocity at the end of 2 minutes. The change in velocity divided by time equals acceleration.
So,
Let d is the distance cover during that time. So,
So, the final speed is 60 m/s and the distance covered during that time is 3600 m.
<span>Assuming the car is travelling in the same direction for the entire hour, the acceleration is zero.</span>
