C does not represent a benefit, so that seems most logical.
A) they comprised.
B) at least ones listening
D) nothings wring with that
Answer:
Actually, gravity is the weakest of the four fundamental forces. Ordered from strongest to weakest, the forces are 1) the strong nuclear force, 2) the electromagnetic force, 3) the weak nuclear force, and 4) gravity.
To solve this exercise it is necessary to apply the equations related to the magnetic moment, that is, the amount of force that an image can exert on the electric currents and the torque that a magnetic field exerts on them.
The diple moment associated with an iron bar is given by,

Where,
Dipole momento associated with an Atom
N = Number of atoms
y previously given in the problem and its value is 2.8*10^{-23}J/T


The number of the atoms N, can be calculated as,

Where
Density
Molar Mass
A = Area
L = Length
Avogadro number


Then applying the equation about the dipole moment associated with an iron bar we have,



PART B) With the dipole moment we can now calculate the Torque in the system, which is



<em>Note: The angle generated is perpendicular, so it takes 90 ° for the calculation made.</em>
Answer:

Explanation:
From the question we are told that:
Far point is 
Near point is 
Therefore
Focal Length

Generally the equation for the Lens is mathematically given by



The gravitational field is the Force divided by the mass
Call g the gravitational fiel, F the force exerted by the earth and m the mass of the telescope.
g = F / m
g=9.1x10^4 N / 1.1 x 10^4 kg = 8.27 N/kg
Note that the unit N/kg is equivalent to m/s^2