Work and Energy Review

Front

What is work in physics?

Back

Work is defined as the transfer of energy that occurs when a force is applied to an object and the object moves in the direction of the force. It is calculated as Work = Force x Distance x cos(θ), where θ is the angle between the force and the direction of motion.

Front

What is kinetic energy?

Back

Kinetic energy is the energy of an object due to its motion. It is given by the formula KE = 1/2 mv², where m is the mass of the object and v is its velocity.

Front

What is potential energy?

Back

Potential energy is the energy stored in an object due to its position or configuration. For gravitational potential energy, it is calculated as PE = mgh, where m is mass, g is the acceleration due to gravity, and h is the height above a reference point.

Front

What is the work-energy principle?

Back

The work-energy principle states that the work done on an object is equal to the change in its kinetic energy. This means that if work is done on an object, its energy will change.

Front

What is the difference between internal and external forces?

Back

Internal forces are forces that act within a system, while external forces are forces that act on a system from outside. For example, friction is an external force acting on a sliding box.

Front

What happens to mechanical energy when friction is present?

Back

When friction is present, mechanical energy is converted into thermal energy, leading to a decrease in the total mechanical energy of the system.

Front

What is gravitational potential energy?

Back

Gravitational potential energy is the energy an object possesses because of its position in a gravitational field, typically relative to the ground.

Front

How does energy conservation apply to a falling object?

Back

As an object falls, its gravitational potential energy decreases while its kinetic energy increases, keeping the total mechanical energy constant (ignoring air resistance).

Front

What is the formula for calculating work done against friction?

Back

Work done against friction can be calculated using the formula Work = Friction Force x Distance.

Front

What is the significance of the energy bar chart?

Back

An energy bar chart visually represents the distribution of different types of energy (kinetic, potential, thermal) in a system, helping to analyze energy transformations.