Answer:
Explanation:
There is reflection ( two times ) from upper and lower surface of the film . In both cases , reflection is from low to high density medium so there is change in phase of 180 twice .
So for constructive interference
2μd = n λ₁ , d is thickness required , λ is wavelength n₁ is order of bright fringe
For destructive interference ( minimum light )
2μd = (2n+1) λ₂/2
n λ₁ =(2n+1) λ₂/2
(2n+1) / 2n = λ₁ / λ₂
= 650 / 505
= 5 / 4 ( approx )
2n = 4
n = 2
2μd = n λ₁
2 x 1.33 x d = 2 x 650 nm
d = 488.72 nm
Explanation:
v = wavelength x frequency
330 = 5 . 10-² m x f
f = 6600 Hz
the frequency that human can hear is about 20 Hz - 20000 Hz
so human can hear the note.
Answer:
A = 62.5 g
using half life formulas, plug in missing variables.
Answer:

Explanation:
The difference between parallel and anti parallel alignment of the z component of an electron's spin magnetic dipole moment is given by

where μ= dipole moment B= strength of magnetic field and θ= angle between direction of magnetic field and dipole
here θ_2 and θ_1 are 180 and 0° respectively.


here μ is bohr magnetron or magnetic moment of an electron = 9.27×10^{-24}
put this value we get


Answer:
Sea-floor spreading occurs in the oceanic ridges. In there, volcanic activity, together with the gradual movement of the bottom, form new oceanic crust. This allows a better understanding of the continental drift explained by the theory of plate tectonics.
The greatest evidence for Sea-floor spreading is the oceanic trenches, the oceanic ridges, the magma protruding to the surface and the new seafloor.
In previous theories, continents were assumed to be transported across the sea. Harry Hess, in the 1960s, proposed the idea that the seabed itself moves as it expands from a central point. The theory is now accepted, and the phenomenon is thought to be caused by convection currents in the upper layer of the mantle.