2. A spherical mirror is to be used in a motion picture projector to form an
inverted, real image 95 times as tall as the picture in a single frame of film.
The image is projected onto a screen 13 m from the mirror. What type of
mirror is required, and how far should it be from the film?

-Spherical Concave mirror

-distance is 0.1368 m

Explanation:

-In physics, magnification is defined as the ratio between the size of the image to the size of the object;

This is also same as;

Given that m=95x, and and the image distance as 13m, the object distance is calculated as:

Hence, the object distance is 0.1368 meters

The image grows bigger when object is moved closer to the mirror, hence , this is a spherical concave mirror

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