Answer:
minimum thickness of the coating = 122.868 nm
Explanation:
Given data
lens index of refraction = 1.29
wavelength = 634 nm
glass index of refraction = 1.53
to find out
minimum thickness of the coating
solution
we have given non reflective coating
so
we know that minimum thickness of the coating formula
minimum thickness of the coating = Wavelength / 4n
here n is coating index of refraction
so put here both value to get thickness
minimum thickness of the coating = Wavelength / 4n
minimum thickness of the coating = 634 / 4 ( 1.29 )
so minimum thickness of the coating = 122.868 nm
<h2>Answer: electrostatic and gravitational force
</h2><h2 />
Mechanical energy remains constant (conserved) if only <u>conservative forces</u> act on the particles.
In this sense, the following forces are conservative:
-Gravitational
-Elastic
-Electrostatics
While the Friction Force and the Magnetic Force are not conservative.
According to this, mechanical energy is conserved in the presence of electrostatic and gravitational forces.
Let the observer be 'd' distance away from the thunderstorm and let light take 't' time to reach the observer
Since the speed of sound and light remains constant in a particular medium, we can use
Speed = Distance/Time
For light,
3 x 10^8 = d/t
t = d/(3 x 10^8) -1
For sound,
339 = d/(t + 30) -2
Putting value from 1 in 2.
d = 10^4 m(approx)
Answer:
Given, Apparent weight(W₂)=4.2N
Weight of liquid displaced (u)=2.5N
Let weight of body in air = W₁
Solution,
U=W₁-W₂
W₁=4.2=2.5=6.7N
∴Weight of body in air is 6.7N
