Physics Lecture Notes on Force, Energy, and Momentum

A series of flashcards covering key concepts in force, energy, and momentum, including definitions, formulas, and laws of motion.

Scalars

Physical quantities that describe only magnitude.

Vectors

Physical quantities that describe both magnitude and direction.

Resultant Vector (R)

The vector that results from adding two or more vectors together.

Pythagorean Theorem

A method used to find the resultant of two perpendicular vectors: $R = \sqrt{x^2 + y^2}$.

Trigonometry

A branch of mathematics used to find angles and lengths in triangles, often used in vector direction calculations.

Resolving Vectors

The process of breaking a vector into its horizontal and vertical components.

Components of a Vector

The projections of a vector along the axes of a coordinate system, often denoted as x and y.

Moment of a Force

The measure of the ability of a force to cause rotation about a point: $\text{Moment} = \text{Force} \times \text{Perpendicular distance to line of action of force}$.

Equilibrium

A state where the sum of all forces acting on an object is zero, leading to no resultant force.

Newton's First Law

An object will remain at rest or travel at a constant velocity unless acted upon by a resultant force.

Newton's Second Law

The acceleration of an object is proportional to the resultant force acting on it, expressed as $F = ma$.

Momentum

The product of an object's mass and velocity: $\text{Momentum} = m \times v$.

Kinetic Energy

The energy possessed by an object due to its motion: $KE = \frac{1}{2} mv^2$.

Work Done (W)

The energy transferred when a force causes an object to move: $W = F \times s \times \cos(θ)$.

Efficiency

A measure of how well a system transforms energy, calculated as: $\text{Efficiency} = \frac{\text{Useful output power}}{\text{Total input power}}$.

Young Modulus

A measure of material stiffness, calculated as the ratio of stress to strain: $E = \frac{\text{Tensile stress}}{\text{Tensile strain}}$.

Elastic and Plastic Deformation

Elastic deformation allows a material to return to its original shape, while plastic deformation results in a permanent change.