In hooke’s law f spring equals k triangle x what does the triangle x stand for

Compression/stretching of the spring

Explanation:

Hook's law gives the relationship between the restoring force on a spring and its compression/stretching:

where

F is the restoring force on the spring

k is the spring constant, which gives a measure of the stiffness of the spring

is the difference between the spring's position and the spring's equlibrium position, so it gives a measure of the compression or the stretching of the spring, measured relative to its equilibrium position

The negative sign in the formula simply means that is a restoring force, so if is positive (stretching) the force goes in the negative direction (towards the equilibrium position), while if is negative (compression), the force goes towards positive direction (towards the equilibrium position).

the answer is a. at the equator

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