Answer:
Second order line appears at 43.33° Bragg angle.
Explanation:
When there is a scattering of x- rays from the crystal lattice and interference occurs, this is known as Bragg's law.
The Bragg's diffraction equation is :
.....(1)
Here n is order of constructive interference, λ is wavelength of x-ray beam, d is the inter spacing distance of lattice and θ is the Bragg's angle or scattering angle.
Given :
Wavelength, λ = 1.4 x 10⁻¹⁰ m
Bragg's angle, θ = 20°
Order of constructive interference, n =1
Substitute these value in equation (1).

d = 2.04 x 10⁻¹⁰ m
For second order constructive interference, let the Bragg's angle be θ₁.
Substitute 2 for n, 2.04 x 10⁻¹⁰ m for d and 1.4 x 10⁻¹⁰ m for λ in equation (1).


<em>θ₁ </em>= 43.33°
Answer:In the decades prior to 1993 there was a robust Pacific herring population in Prince William Sound (PWS). Not only are these forage fish a key link in the complex food web of PWS, but they supported a lucrative early-season commercial fishery that brought the communities of the Sound to life each spring. By 1994, that fishery was closed and only briefly reopened for two years in the late 1990s. The current, approximately 10,000-ton biomass, is tiny compared to the peak value of 130,000 tons or the long-term average prior to the collapse of around 65,000 ton.
Explanation:
Vector it always consists to size(magnitude) and direction
Answer:
Speed, mass and acceleration
Explanation:
A scalar quantity is a quantity that has only magnitude but no direction while a vector quantity has both magnitude and direction.
According to the question, the row that has two scalars and one vector is speed, mass and acceleration.
The two scalars in this row are speed and mass while the vector quantity there is the acceleration.
Acceleration has direction since it possess direction. A body accelerating will do so in a particular direction. Speed and mass doesn't possess any direction. Mass only specify the magnitude of the body but no clue as to which direction is the body moving towards.
Speed also only specify the
total distance covered with respect to time but not the direction of the direction.