Arailroad freight car, mass 15 000 kg, is allowed to coast along a level track at a speed of 2.0 m/s. it collides and couples with a 50 000-kg loaded second car, initially at rest and with brakes released. what percentage of the initial kinetic energy of the 15 000-kg car is preserved in the two-coupled cars after collision

23.0760769 %

Explanation:

= Mass of freight car = 15000 kg

= Mass of second car = 50000 kg

= Velocity of freight car = 2 m/s

= Velocity of second car = 0

v = Combined mass velocity

As the linear momentum of the system is conserved we have

The initial kinetic energy

Final kinetic energy

The percentage is given by

The change in percentage of initial kinetic energy is 23.0760769 %

the earths atmosphere is made up of nitrogen and oxygen. solids can turn into gasses through a process called sublimation. sublimation is the transition of a substance directly from the solid to the gas phase, without passing through the intermediate liquid phase.

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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.

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from wikipedia