Physics: Forces, Vectors, Mass, Weight, and Motion

Vocabulary-style flashcards covering vectors, scalars, Newton's laws of motion, mass and weight, common forces, and ticker-tape timer motion analysis.

Scalar quantity

A physical quantity that possesses only magnitude and a unit, such as speed, distance, time, energy, and mass.

Vector quantity

A physical quantity that possesses magnitude, a unit, and a direction, such as velocity, acceleration, force, and displacement.

Parallelogram rule

A method using a scale drawing to determine the resultant of two vectors that do not act along the same straight line.

Mass

The amount of stuff in an object and its resistance to a change in motion when a force is applied, measured in kilograms ($kg$).

Weight

The gravitational force exerted on an object mass ($W = mg$), measured in Newtons ($N$).

Gravitational field strength ($g$)

The gravitational force per unit mass exerted on an object, which equals $10\,N/kg$ near Earth's surface, $1.6\,N/kg$ on the Moon, and $3.7\,N/kg$ on Mars.

Balance

An instrument used to compare or measure the mass of an object by balancing it against standard masses or converting gravitational force on an electronic sensor.

Resultant force

A single force that is equivalent to the vector sum of all individual forces acting on an object.

Newton's Second Law of Motion

The law stating that the resultant force acting on an object equals its mass multiplied by its acceleration ($F = ma$).

Newton ($N$)

The SI unit of force, defined as the force required to give a mass of $1\,kg$ an acceleration of $1\,m/s^2$.

Force

A push or pull exerted on an object that can change its size, shape, or motion; it is a vector quantity measured in Newtons ($N$).

Friction

A contact force acting between two sliding or moving surfaces that opposes motion and converts kinetic energy into heat energy.

Upthrust

The upward force exerted by a fluid (liquid or gas) that enables objects to float.

Tension

The pulling force transmitted through or present in a stretched material.

Thrust

The forward driving force produced by an engine, such as an aircraft engine.

Air resistance

A specific type of friction force exerted by air that opposes the movement of an object travelling through it.

Newton meter

A measuring device containing a spring used to measure the magnitude of a force in Newtons ($N$).

Newton's First Law of Motion

The law stating that an object remains stationary or continues moving at a steady speed in a straight line unless acted upon by an external resultant force.

Balanced forces

Forces acting on an object that are equal in size and opposite in direction, producing a net resultant force of zero and no change in motion.

Terminal velocity

The maximum steady velocity reached by a falling object when the upward force of air resistance equals its downward weight.

Ticker-tape timer

A device using a vibrating bar to punch dots onto a moving paper tape at regular intervals ($50\,\text{dots per second}$) to record motion.

Ticker tape dot pattern

The pattern of dot spacing on a ticker tape, where equal spacing indicates constant speed and increasing spacing indicates acceleration.