A boat is moving at the rate of 15.0 meters per second. It’s speed is then decreased uniformly to 3.0 meters per second. It takes 4 seconds for the speed to decrease. What is the magnitude of the deceleration of the car ?

-3 m/s²

Explanation:

The formula for deceleration is given as the change in speed over a period of time

Given that,

Initial speed = 15 m/s

Final speed = 3 m/s

change in speed= 3-15= -12 m/s

Time taken= 4 sec

Deceleration = -12/4 = -3 m/s²

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