Answer:
7.46 J/kg/K
Explanation:
The heat absorbed or lost is:
q = mCΔT
where m is the mass, C is the heat capacity, and ΔT is the change in temperature.
Given q = 15.0 J, m = 0.201 kg, and ΔT = 10.0 °C:
15.0 J = (0.201 kg) C (10.0 °C)
C = 7.46 J/kg/°C
Which is the same as 7.46 J/kg/K.
 
        
                    
             
        
        
        
Answer:
95.0 colomb
Explanation:
Make sure to understand the concept
 
        
             
        
        
        
First we find the energy level with the following formula, where a is the energy level, n1 is the final energy level, n2 is the starting energy level and r is Rydberg's constant in Joules

We insert the values


The wavelength is found with this formula, where h is Planck's constant and c is the speed of light

Finally we insert the values

Which is the same as 93.8 nm
 
        
             
        
        
        
the electric force decreases because the distance has an indirect relationship to the force
Explanation:
The electric force between two objects is given by

where
k is the Coulomb's constant
q1 and q2 are the charges of the two objects
r is the distance between the two objects
As we can see from the formula, the magnitude of the force is inversely proportional to the square of the distance: so, when the distance between the object increases, the magnitude of the force decreases.
 
        
                    
             
        
        
        
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.