Two protons are 1 × 10−10 m apart (about one atomic radius). Which interaction between two protons is stronger, the gravitational attraction or the electric repulsion? Note that since both the gravitational and electric forces depend on the inverse square distance, this comparison holds true at all distances, not just at a distance of 1 × 10−10 m. Use the accurate values of G = 6.67 × 10−11 N·m2/kg2, proton mass of 1.67 × 10−27 kg, and electron mass of 9.11 × 10−31 kg.

a) First, calculate the electric force |Felec| = ___ N
b) Next, calculate the gravitational force |F grav| = ___ N
c) Calculate the ratio of the two forces |Felec|/|Fgrav| = ___

compass can be used day and night, cloudy or sunny

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