Gold, which has a density of 19.32 g/cm3, is the most ductile metal and can be pressed into a thin leaf or drawn out into a long fiber. (a) if a sample of gold with a mass of 7.158 g, is pressed into a leaf of 2.810 μm thickness, what is the area of the leaf? (b) if, instead, the gold is drawn out into a cylindrical fiber of radius 2.600 μm, what is the length of the fiber?

area  of the leaf is 0.13167 m²

length of the fiber is 17431.1235 m

Explanation:

Given data

gold density = 19.33 g/cm3

gold mass = 7.158 g

thickness = 2.810 μm =  2.810 × m

radius = 2.600 μm

to find out

area of the leaf and  length of the fiber

solution

first we calculate volume from density

we know density formula that is mass / volume

so volume = mass / density

put these value

volume = 7.158  /  19.33

volume = 0.370 cm³ = 0.370 × m³

so area = volume / thickness

area = 0.370 ×  / 2.810 ×

area = 0.13167 m²

and

area of fiber is = πr²

so area =  π(2.600× )²

area = 2.12264 ×

so length = volume / area

put value

length = 0.370 × / 2.12264 ×

length is 17431.1235 m

electromagnetic shielding is the practice of reducing the electromagnetic field in a space by blocking the field with barriers made of conductive or magnetic materials. shielding is typically applied to enclosures to isolate electrical devices from their surroundings, and to cables to isolate wires from the environment through which the cable runs. electromagnetic shielding that blocks radio frequency electromagnetic radiation is also known as rf shielding.

the shielding can reduce the coupling of radio waves, electromagnetic fields and electrostatic fields. a conductive enclosure used to block electrostatic fields is also known as a faraday cage. the amount of reduction depends very much upon the material used, its thickness, the size of the shielded volume and the frequency of the fields of interest and the size, shape and orientation of apertures in a shield to an incident electromagnetic

from wikipedia