Answer:
By looking at the graph it looks like its decreasing but you may want to re- read the question to make sure that I am correct.I hope that this helps!
Explanation:
Answer: The energy incident on the solar panel during that day is
.
Explanation:
Given: Mass = 250 kg
Initial temperature = 
Final temperature = 
Specific heat capacity = 4200 
Formula used to calculate the energy is as follows.

where,
q = heat energy
m = mass of substance
C = specific heat capacity
= initial temperature
= final temperature
Substitute the values into above formula as follows.

As it is given that water absorbs 25% of the energy incident on the solar panel. Hence, energy incident on the solar panel can be calculated as follows.

Thus, we can conclude that the energy incident on the solar panel during that day is
.
Answer:
= 4
Explanation:
To solve this exercise we will use Bohr's atomic model
= - 13.606 / n² [eV]
The transition from level n = 2 to level n = 1 is valid
= - 13.606 [¼ -1/1]
= 10.2045 eV
Bohr's model for atoms with only one electron is
= -13.606 Z² / n²
Where Z is the atomic number of the atom.
In this case the helium atom has an atomic number of Z = 2 from the level n₀ = 2 let's look up to what level it reaches
ΔE = -13.606 [4 /
² - 4/4]
4 /
² = -ΔE / 13.606 + 1
4 /
² = -10.2045 / 13.606 +1 = -0.75 +1
4 /
² = 0.25
= √ 4 / 0.25
= 4
Answer:
f =1 10⁸ Hz
Explanation:
The speed of an electromagnetic wave is given by
c = Lam f
In our case, the wavelength is 3.0 m, so we can clear the frequency
f = c / Lam
f = 3 108/3.
f =1 10⁸ Hz