Work and Energy (AP Physics 1)

Front

What is work in physics?

Back

Work is defined as the product of the force applied to an object and the distance over which that force is applied in the direction of the force. Mathematically, W = F × d × cos(θ), where θ is the angle between the force and the direction of motion.

Front

What is the formula for kinetic energy (KE)?

Back

The formula for kinetic energy is KE = 1/2 mv², where m is the mass of the object and v is its velocity.

Front

What is potential energy (PE)?

Back

Potential energy is the energy stored in an object due to its position or configuration. For gravitational potential energy, 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 relationship between work and energy?

Back

Work done on an object results in a change in its energy. The work-energy principle states that the work done by the net force acting on an object equals the change in its kinetic energy.

Front

What is the significance of the area under a force vs. position graph?

Back

The area under a force vs. position graph represents the work done by the force over that distance.

Front

What is the unit of work in the International System of Units (SI)?

Back

The unit of work is the joule (J), which is defined as one newton-meter (1 J = 1 N·m).

Front

How does the angle of force application affect work done?

Back

The work done by a force is maximized when the force is applied in the same direction as the motion (θ = 0°). If the force is perpendicular to the direction of motion (θ = 90°), no work is done.

Front

What is the work done by a constant force?

Back

The work done by a constant force can be calculated using the formula W = F × d × cos(θ), where F is the magnitude of the force, d is the distance moved in the direction of the force, and θ is the angle between the force and the direction of motion.

Front

What is the principle of conservation of energy?

Back

The principle of conservation of energy states that energy cannot be created or destroyed, only transformed from one form to another. The total energy in a closed system remains constant.

Front

What is the difference between conservative and non-conservative forces?

Back

Conservative forces (like gravity) do work that is independent of the path taken, and they can store energy (potential energy). Non-conservative forces (like friction) depend on the path and dissipate energy as heat.