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Where are the statements?
Answer: the minimal force that you need to apply to move the bureau is F = 198.45N
Explanation:
If you want to move an object, you need to apply a force that is bigger than the force of the statical friction.
The force of statical friction can be written as.
Ff = k*N
where k is the coefficient of static friction, in this case, k = 0.45, and N is the normal force between the object and the surface.
In this case, the normal force is the weight of the bedroom bureau, this is:
N = m*g = 45kg*9.8m/s^2 = 441N
Then the force is:
Fr = 0.45*441N = 198.45N
This means that the minimal force that you need to apply to move the bureau is F = 198.45N
and after this point, the force of friction will work wit the kinetic coefficient of friction, that usually is smaller than the statical one.
Use light-years as the unit of measurement <span />
Answer:
D) θ₂= 36. 6º
Explanation:
In this diffraction experiment it is described by the equation
sin θ = m λ
The first dark strip occurs for m = 1 and since the angle is generally small we can approximate sine to the value of the angle
θ₁ = λ/ a
This equation is valid for linear slits, in the case of a circular slit the problem must be solved in polar coordinates, so the equation changes slightly
θ₂ = 1.22 λ / a
In the proposed exercise we start with a linear slit of width a, where tes1 = 30º and end with a circular slit of the same diameter
θ₂ = 1.22 λ / a
Let's clear (Lam/a) of equalizing the two equations
θ₁ = θ₂/ 1.22
θ₂ = 1.22 θ₁
θ₂ = 1.22 30
θ₂= 36. 6º
When reviewing the correct results is D
