Answer:

Explanation:
The energy of a single photon is given by:

where
h is the Planck constant
c is the speed of light
is the wavelength
For the photon in this problem,

So, its energy is

One mole of photons contains a number of photons equal to Avogadro number:

So, the total energy of one mole of photons is

Answer:
F' = 64 F
Explanation:
The electric force between charges is given by :

Where
q₁ and q₂ are charges
r is the distance between charges
When each charge is doubled and the distance between them is 1/4 its original magnitude such that,
q₁' = 2q₁, q₂' = 2q₂ and r' = (r/4)
New force,

Apply new values,

So, the new force becomes 64 times the initial force.
Explanation:
potential energy = mass × gravity force × height
=20 × 10 × 25
= 5000 joules
What is your choses .becuse it mit be a place
Answer:
ΔK.E = 2.5 × 10⁻³ J
Explanation:
Given data in the question, we have:
Charge of the particle, q = 5.0 μC = 5 × 10 ⁻⁶ C
Initial speed of the particle, v = 55 m/s
The potential difference, ΔV = 500 V
Now, the gain in kinetic energy is given as
ΔK.E = q × ΔV
on substituting the values in the above formula, we get
ΔK.E = 5 × 10 ⁻⁶ C × 500 V
or
ΔK.E = 2.5 × 10⁻³ J