The magnetic field within a long, straight solenoid with a circular cross section and radius r is increasing at a rate of db/dt. ( include pictures and graphs)

a) what is the rate of change of flux through a circle with radius r1 inside the solenoid, normal to the axis of the solenoid, and with center on the solenoid axis?

b) find the magnitude of the induced electric field inside the solenoid, at a distance r1 from its axis.

c) what is the magnitude of the induced electric field outside the solenoid, at a distance r2 from the axis?

d) what is the magnitude of the induced emf in a circular turn of radius r/2 that has its center on the solenoid axis?

e) what is the magnitude of the induced emf if the radius in part d) is r?

f) what is the induced emf if the radius in part d is 2r?

answer: the answer is 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

it is a negative acceleration