Bohr's equation for the change in energy is

where
h = Planck's constant
c == the velocity of light
λ = wavelength.
The velocity is related to wavelength and frequency, f, by
c = fλ
Let us examine the given answers on the basis of the given equations.
a. As λ increases, f decreases and ΔE decreases.
TRUE
b. As λ increases, f increases and ΔE increases.
FALSE
c. As λ increases, f increases and ΔE decreases.
FALSE
Answer:
As the wavelength increases, the frequency decreases and energy decreases.
Answer:
Yes, it's correct
Explanation:
Newton's second Law states that the acceleration of an object is proportional to the net force applied on it, according to the equation:

where
F is the net force on the object
m is the mass of the object
a is the acceleration of the object
We can re-arrange the previous equation in order to solve explicitely for a, the acceleration, and we find:

So, we see that the acceleration is proportional to the net force and inversely proportional to the mass of the object.
The answer is C. an electron in an orbit has a fixed energy.
Answer and Explanation:
The main source of earth magnetic field is the metals and iron present in earth crust these metals are mainly found in liquid state in earth crust and we know that whenever there is spinning of these liquid metals then there will magnetic field generate, So the main source of earth magnetic field is the metals present in earth crust.
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