First of all, we can find the mass of the person, since we know his weight W:

And so

We know for Newton's second law that the resultant of the forces acting on the person must be equal to the product between the mass and the acceleration a of the person itself:

There are only two forces acting on the person: his weight W (downward) and the vincular reaction Rv of the floor against the body (upward). So we can rewrite the previous equation as

We know the acceleration of the system,

(upward, so with same sign of Rv), so we can solve to find the value of Rv, the normal force exerted by the elevator's floor on the person:
Answer:
Explanation:
A simple light microscope uses light for imaging of objects where as a transmission electron microscope uses a monochromatic beam of electrons.
This beam is passed by a magnetic field which is very strong and thus act as a lens.
Its resolution of very high which is about 0.2 nanometers because of the separation between two atoms.
Because of this reason its resolution is about 1000 times greater than light microscope.
Answer:Thus, The magnetic field around a current-carrying wire is <u><em>directly</em></u> proportional to the current and <u><em>inversely</em></u> proportional to the distance from the wire. If the current triples while the distance doubles, the strength of the magnetic field increases by <u><em>one and half (1.5)</em></u> times.
Explanation:
Magnetic field around a long current carrying wire is given by

where B= magnetic field
permeability of free space
I= current in the long wire and
r= distance from the current carrying wire
Thus, The magnetic field around a current-carrying wire is <u><em>directly</em></u> proportional to the current and <u><em>inversely</em></u> proportional to the distance from the wire.
Now if I'=3I and r'=2r then magnetic field B' is given by

Thus If the current triples while the distance doubles, the strength of the magnetic field increases by <u><em>one and half (1.5)</em></u> times.
Let there be N number of wires.
Maximum tension a wire can withstand = 100 lb
so, Total tension N wires can withstand = 100 N
now, total tension in N wires = Maximum weight of bucket
100 N = W
so, W = 100N
W is the weight of bucket and 100N is its maximum value.
<span>Using Coulomb's law: k*(-0.3)*(-0.3)/(d^2)=19.2
D is the distance between the two negative charges</span>