Please help quick i’ll mark you The equation below shows how to calculate work done by an applied force. W equals the work done in joules (J), F equals the applied force in newtons (N), and d equals the distance in meters (m) over which the force is applied.

W = F × d

This equation can be arranged to calculate the applied force instead:
F = W ÷ d

A scientist was performing some experiments to test the designs of some simple machines. One of her experiments involved a pulley. During the experiment, a total of 2,000 J of work was done to lift a crate 5 m straight up off the floor.

Ignoring the effects of friction, determine the applied force needed to lift the crate.
A.
2,005 N
B.
400 N
C.
10,000 N
D.
1,995 N

The solutions to this exercise is B. 400N

a and c

c is 100% but i am confused in a

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