We use the Planck’s formula:
E = hv
where,
E = energy, h = planck’s constant = 6.6x10^-34 J s, v =
frequency in Hz (Hz = 1 / s)
Subsituting the values to find for E:
E = (6.6×10^-34 J s) * 9.85×10^14 / s
E = 6.5x10^-19 J
The correct answer is:
sixteen times
In fact, the distance between charge q and the source S is 1 unit. Instead, the distance between charge p and the source S is 4 units. The magnitude of the electrostatic force is inversely proportional to the square of the distance between the charge and the source:

where r is the distance. If we take the force between q and S as reference, we have r=1, so that

while the force between p and S is

Therefore, we see that the force exerted between q and S is 16 times the force exerted between p and S.
Answer:
Minimum angular spread (in rad) = 547.45 x 10⁻⁶ rad
Explanation:
GIven;
Wavelength of manganese vapor laser beam = 534 nm = 534 x 10⁻⁹ m
Diameter = 1.19 mm = 1.19 x 10⁻³ m
Find:
Minimum angular spread (in rad)
Computation:
Minimum angular spread (in rad) = 1.22[Wavelength / Diameter]
Minimum angular spread (in rad) = 1.222[(534 x 10⁻⁹) / (1.19 x 10⁻³)]
Minimum angular spread (in rad) = 2[448.73 x 10⁻⁶]
Minimum angular spread (in rad) = 547.45 x 10⁻⁶ rad