While driving north at 25 m/s during a rainstorm you notice that the rain makes an angle of 38° with the vertical. while driving back home moments later at the same speed but in the opposite direction, you see that the rain is falling straight down. from these observations, determine the speed and angle of the raindrops relative to the ground.

Explanation:

Given

velocity of driver =25 m/s w.r.t ground towards north

driver observes that rain is making an angle of with vertical

While returning =25 m/s w.r.t. ground towards south

suppose =velocity of rain drop relative car while car is going towards north

=velocity of rain drop relative car while car is going towards south

z=vector sum of

Now from graph

therefore magnitude of z is given by

Thus rain drops make an angle of w.r.t to ground

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