Introduction to Work and Energy

Flashcards covering key concepts about work, energy, and related principles in physics.

Work (W)

The product of force, displacement, and the cosine of the angle between the force and displacement.

Force (F)

A vector quantity that causes an object to accelerate, measured in Newtons (N).

Displacement (d)

The distance moved by an object in a specific direction.

Angle (θ)

The angle between the force applied and the displacement of the object.

Positive Work

Work done when the force and displacement are in the same direction, resulting in a positive value.

Negative Work

Work done when the force and displacement are in opposite directions, resulting in a negative value.

Zero Work

Work done when the angle between force and displacement is 90 degrees; no movement in the direction of the force.

Kinetic Energy (KE)

The energy associated with the motion of an object, calculated as KE = 1/2 mv², where m is mass and v is velocity.

Gravitational Potential Energy (PE_g)

The energy stored in an object due to its height above a reference point, calculated as PE_g = mgh.

Elastic Potential Energy (PE_e)

The energy stored in a compressed or stretched spring, calculated as PE_e = 1/2 kx², where k is the spring constant and x is the displacement.

Conservation of Mechanical Energy

The principle stating that the total mechanical energy (kinetic + potential) remains constant if only conservative forces act.

Frictional Work (W_f)

Work done by the force of friction, often opposed to the motion, calculated as Wf = Ff d cos(180°).

Angle of Friction (θ_f)

The angle used to calculate the force of friction, often derived from the coefficient of friction.

Spring Constant (k)

A measure of the stiffness of a spring, defined as the force required to compress or extend it by a unit length.

Mechanical Energy (ME)

The sum of kinetic and potential energy in a system.

Magnitude

The size or quantity of a vector without regard to its direction.

Work-Energy Theorem

The principle that the work done on an object is equal to the change in its kinetic energy.

Free Body Diagram (FBD)

A graphical illustration used to visualize the forces acting on an object.