Question

A person of 82 kg is in an elevator. If the elevator is moving at a speed of 5m/s, what’s the person’s kinetic energy.

Answer 1

Answer:

The person’s kinetic energy is 1,025 J

Explanation:

Kinetic energy is a form of energy. It is defined as the energy associated with bodies that are in motion and this energy depends on the mass and speed of the body.

Kinetic energy is defined as the amount of work necessary to accelerate a body of a given mass and in a position of rest, until it reaches a given speed. Once this point is reached, the amount of accumulated kinetic energy will remain the same unless there is a change in speed or the body returns to its state of rest by applying a force.

Kinetic energy is represented by the following formula:

$Ec=\frac{1}{2}*m*v^{2}$

where Ec is kinetic energy, which is measured in Joules (J), m is mass measured in kilograms (kg), and v is velocity measured in meters over seconds (m/s).

In this case:

• Ec= ?
• m= 82 kg

• v= 5 $\frac{m}{s}$

Replacing:

$Ec=\frac{1}{2}*82 kg*(5\frac{m}{s} )^{2}$

Solving:

Ec= 1,025 J

The person’s kinetic energy is 1,025 J