Answer:
L = a 1,929 10⁴ m
a = 0.1 mm = 0.1 10⁻³ m, L = 1,929 m
Explanation:
The diffraction phenomenon is described by the expression
a sin θ = m λ
Let's use trigonometry to find the breast
tan θ = y / x
As the angles are very small
tan θ = sin θ/ cos θ = sin θ = y / x
We replace
a y / L = m λ
L = a y / m λ
The red light has a wavelength of Lam = 700 nm = 700 10⁻⁹ m, in the third pattern it is m = 3
L = a 4.05 10⁻² / (3 700 10⁻⁹)
L = a 1,929 10⁴ m
To give a specific value we must know the width of the slit, suppose a value of a = 0.1 mm = 0.1 10⁻³ m
L = 1,929 m
Explanation:
I think this would help you. Read this and make your own answer ok.
As the box is moving with a constant velocity, the two forces acting on the box are canceling each other.
Then friction force = 80 Newtons but in the opposite direction.
Friction force = Mu * Normal force exerted by ground = Mu * weight of box
So we find Mu.
Mu = coefficient of friction between box and horizontal surface
= Force of friction / weight = 80 / 50 * 9.81 = 0.163
When an identical box is placed on top, the force of friction is
= Mu * total weight = 0.163 * (50+50) * 9.81 = 159.9 Newtons
The answer is "friction and air resistance" gravity does some of the work by keeping the object from floating away, but friction and air resistance does the biggest part. Friction is how rough the ground it meaning on tile, dirt, grass, etc... that would slow down the object and air resistance is the gravity pushing on the object also making it stop.
Hope this helps!