Energy Concepts and Calculations

Front

What is the formula to calculate power?

Back

Power (P) = Work (W) / Time (t)

Front

Define mechanical energy.

Back

Mechanical energy is the sum of potential energy and kinetic energy in a system.

Front

What is a conservative force?

Back

A conservative force is one where the work done does not depend on the path taken, only on the initial and final positions.

Front

What is a non-conservative force?

Back

A non-conservative force is one where the work done depends on the path taken, such as friction.

Front

How do you calculate work done by a force?

Back

Work (W) = Force (F) x Displacement (d) x cos(θ), where θ is the angle between the force and displacement.

Front

What is the unit of power?

Back

The unit of power is the Watt (W), which is equivalent to one Joule per second.

Front

If a machine has a power output of 800 W, how long does it take to perform 6000 J of work?

Back

7.5 seconds.

Front

What is the relationship between kinetic energy and velocity?

Back

Kinetic energy (KE) = 1/2 mv², where m is mass and v is velocity.

Front

What is the principle of conservation of energy?

Back

The principle states that energy cannot be created or destroyed, only transformed from one form to another.

Front

Calculate the velocity of an object with a mass of 55 kg after a force of 45 N is applied over a displacement of 10 m, starting from rest.

Back

4.05 m/s.