You want to use a rope to pull a 12-kg box of books up a plane inclined 30∘ above the horizontal. The coefficient of kinetic friction is 0.27. The rope pulls parallel to the incline. What force do you need to exert on the rope if you want to pull the box at constant speed.

b

step-by-step explanation: a third of 24 is 8, 8 times 3 is 24 so 8 - 2 would be 6

fgravity=10x10=100n case 1

fgravity=30x20=600n case 2

6 times more

it breaks and dirupture other materials and other sencews from the bottom

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