Answer:
(1) En to n-1 = 0.55 ev
(2) En-1 to n-2 = 0.389 ev
(3) ninitial =4
(4) L =483.676 ×10^-11 nm
(5) λlongest= 1773.33 nm
Explanation:
Detailed explanation of answer is given in the attached files.
Answer:
number of electrons = 2.18*10^18 e
Explanation:
In order to calculate the number of electrons that move trough the second wire, you take into account one of the Kirchoff's laws. All the current that goes inside the junction, has to go out the junction.
Then, if you assume that the current of the wire 1 and 3 go inside the junction, then, all this current have to go out trough the second junction:
(1)
i1 = 0.40 A
i2 = 0.75 A
you solve the equation i3 from the equation (1):

Next, you take into account that 1A = 1C/s = 6.24*10^18
Then, you have:

The number of electrons that trough the wire 3 is 2.18*10^18 e/s
Answer:
<h2>9.375Nm</h2>
Explanation:
The formula for calculating torque τ = Frsin∅ where;
F = applied force (in newton)
r = radius (in metres)
∅ = angle that the force made with the bar.
Given F= 25N, r = 0.75m and ∅ = 30°
torque on the bar τ = 25*0.75*sin30°
τ = 25*0.75*0.5
τ = 9.375Nm
The torque on the bar is 9.375Nm
Answer:
0.214 m
Explanation:
In order for the bag to levitate and not fall down, the electrostatic force between the bag and the balloon must balance the weight of the bag.
Therefore, we can write:

where
k is the Coulomb constant
is the charge on the balloon
is the charge on the bag
r is the separation betwen the bag and the balloon
is the mass of the bag
is the acceleration due to gravity
Solving for r, we find the distance at which the bag must be held:

Answer:b)1770 kWh
Explanation:
Given
volume of water 
Temperature rise 

also 1 kg mass is approximately is 1 gallon
therefore 40,000 gallon is equivalent to 3.8\times 40000 kg
heat Required to raise temperature is




