Question 7: An astronaut is drifting away from the space shuttle at a velocity of 1.1 m/s.
Luckily he has his gun with him and he decides to fire his
gun's 30 g bullets as a means of returning to his ship. The mass of the astronaut
and his spacesuit is 123 kg, his gun has a mass of 12 kg and the bullets leave his
gun at 250 m/s.

b) What is the approximate minimum number of bullets that he will need to fire to begin drifting
back to the ship?

force is mass*acceleration.

we have a very small mass: 11.4*0.001 kg

if we want 0.035n of force, we need an acceleration:

0.035 = 11.4*0.001*a

a = 0.035/(11.4*0.001) m/s^2

a straight line sloped

what is the speed of a softball that travels 20m in 2secs

speed = 20/2 = 10 m/s

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