A 2200kg car travelling at 30ms collides with another 2200kg car that is at rest. The two bumpers lock and the cars move forward together. What is their final velocity?

Hockey puck A (2kg) travels with a velocity of 40ms to the right when it collides with hockey puck B (1.6kg), which was originally at rest. After the collision, puck A is stationary. Assume no external forces are in play and that the momentum of the pucks are conserved. What is the final velocity of puck B after the collision?

A 12kg ball moving at 37ms strikes a second ball at rest. After the collision the 12kg ball is moving with a velocity of 19ms and the second ball is moving with a velocity of 4ms. What is the mass of the second ball?

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