Answer:
Isolated or Closed system, both are correct
Answer:
t< 75 nm
Explanation:
A soap bubble is a thin film where when the beam enters the film it has a 180º phase change due to the refractive index and the wavelength changes between
λ = λ₀ / n
In the case of constructive interference in the curve of the spherical film it is
2 nt = (m + ½) λ₀
Where t is the thickness of the film and n the refractive index that does not indicate that we use that of water n = 1.33, m is an integer. The thickness of the film for the first interference (m = 0) is
t = λ₀ / 4 n
A thickness less than this gives destructive interference.
Let's look for the thickness for the visible spectrum
Violet light λ₀ = 400 nm = 400 10⁻⁹ m
t₁ = 400 10⁻⁹ / 4 1.33
t₁ = 75.2 10-9 m
Red light λ₀ = 700 nm = 700 10⁻⁹ m
t₂ = 700 10⁻⁹ / 4 1.33
t₂ = 131.6 10⁻⁹ m
Therefore, for all wavelengths to have destructive interference, the thickness must be less than 75 10⁻⁹ m = 75 nm
b) a film like eta is very thin, it is achieved when gravity thins the pomp, but any movement or burst of air breaks it,
Answer:
B. Axial stress divided by axial strain
Explanation:
Elasticity:
It is the tendency of an object to deform along the axis when an opposing force is applied without facing permanent change in shape.
Plasticity:
When an object crosses the elasticity limit, it enters plasticity where the change due to stress is permanent and the object might even break.
Yield strength:
Yield strength is the point of maximum bearable stress that indicates the limit of elasticity.
Our case:
As the stress applied is less than the yield strength, the rod is still in the elasticity state and its modulus can be calculated.
Modulus of Elasticity = Stress along axis/Ratio of change in length to original length
Axial strain is basically the ratio of change in length to original length.
So, Modulus of Elasticity = Axial Stress/ Axial Strain
