Physics Lecture Notes: Force, Motion, Work, Energy, and Momentum

These flashcards cover key terms and concepts from the physics lecture notes on force, motion, work, energy, and momentum.

Force

A push or pull exerted by an object on another object; a vector quantity with magnitude and direction.

Net Force

The vector sum of all forces acting on a body.

Contact Forces

Forces that require human contact to interact with an object.

Field Forces

Forces that do not require any human contact with an object.

Newton's First Law of Motion

An object will stay at rest or continue moving at a constant speed unless acted upon by an external force.

Newton's Second Law of Motion

The acceleration of an object depends on the net force applied and its mass; given by the equation F = ma.

Newton's Third Law of Motion

For every action, there is an equal but opposite reaction.

Mass

The amount of matter a body contains, constant in value.

Weight

The force exerted by Earth's gravity, a vector quantity directed towards the center of the Earth.

First Condition of Equilibrium

The sum of all net external forces on an object must be zero.

Free Body Diagram

A diagram showing the object separated from its surroundings along with the magnitude and direction of all forces acting on it.

Friction

A force that resists motion between materials in contact.

Static Friction

The block remains stationary; net forces are balanced and equal to zero.

Kinetic Friction

The friction when a block is moving, can cause sliding or rolling effects.

Laws of Friction

1. Static friction is greater than kinetic friction; 2. Friction acts parallel to surfaces; 3. Friction is independent of contact area and speed.

Newton's Law of Universal Gravitation

Every particle in the Universe attracts every other particle with a force proportional to the product of their masses and inversely proportional to the square of the distance between them.

Kepler's First Law

All planets move in elliptical orbits with the Sun at one focus.

Work (Physics)

The dot product of force and displacement in the direction of that force.

Kinetic Energy (K)

Energy possessed by a body because of its motion, calculated with the formula K = 1/2 mv^2.

Potential Energy (U)

Energy possessed by a body due to its position or configuration.

Work-Energy Theorem

The work done on a body changes its motion, represented mathematically as W = ΔK.

Power (P)

The rate of doing work, measured in Watts.

Conservation of Energy

Energy can change forms, but it is neither created nor destroyed; the total energy of a closed system remains constant.

Momentum (p)

The product of an object's mass and velocity.

Impulse (I)

The product of force and the time duration of the impact, calculated as I = FΔt.

Types of Collisions

Elastic and inelastic; total momentum is conserved in both, but total kinetic energy is only conserved in elastic collisions.

Coefficient of Restitution (e)

A measure of the elasticity of a collision between two objects.