The spherical surface of a plane -convex lens of radius of curvature R...
We know for minima in newtons ring
where n=1. 2. 3
(a) for n = 15
e = thickness of liquid film = x
2/2R
X = radius of ring
R = radius of curvature of lens one gets
Given μ = 1.5
R = 2m
n = 15
So,
So. λ = 0.25 * 10
-6 m
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The spherical surface of a plane -convex lens of radius of curvature R...
We know for minima in newtons ring
where n=1. 2. 3
(a) for n = 15
e = thickness of liquid film = x
2/2R
X = radius of ring
R = radius of curvature of lens one gets
Given μ = 1.5
R = 2m
n = 15
So,
So. λ = 0.25 * 10
-6 m
The spherical surface of a plane -convex lens of radius of curvature R...
To find the radius of the fifteenth dark Newton's ring, we can use the formula:
r = sqrt(n * λ * R)
Where:
r = radius of the Newton's ring
n = order of the ring (in this case, 15)
λ = wavelength of the light
R = radius of curvature of the lens
First, let's find the wavelength of the reflected light. We know that the refractive index of the flat plate is 1.6, so the speed of light in the flat plate will be:
v = c / n
Where:
v = speed of light in the flat plate
c = speed of light in vacuum
n = refractive index of the flat plate
Using the given refractive index of the flat plate (1.6), we can calculate the speed of light in the flat plate:
v = c / 1.6
Next, let's find the wavelength of the reflected light using the formula:
λ = v / f
Where:
λ = wavelength of the reflected light
v = speed of light in the flat plate
f = frequency of the light
The frequency of the light remains constant, so we can use the same frequency as the incident light. Let's say the frequency is f.
Now, we can substitute the values into the formula for the radius of the fifteenth dark Newton's ring:
r = sqrt(n * λ * R)
Substituting the values we have calculated, we can find the radius of the fifteenth dark Newton's ring.