Physics Vocabulary Flashcards

These flashcards cover key vocabulary terms and concepts from physics, focusing on kinematics, forces, energy, motion, electricity, and waves.

Displacement

Change in position of an object.

Example: A car moves 10 meters east and then 5 meters west. The total displacement is 5 meters east.

Velocity

Speed with direction; can be average or instantaneous.

Example: The car travels at 20 m/s north.

Acceleration

Rate of change of velocity.

Example: A car going from 0 to 60 mph in 5 seconds is accelerating.

Free Fall

Motion under gravity alone.

Example: A skydiver in free fall before opening the parachute.

Projectile Motion

Motion in two dimensions under gravity.

Example: A soccer ball follows a curved path when kicked.

Force

A push or pull acting on an object.

Example: Pulling a wagon or pushing a door open.

Newton’s First Law (Inertia)

An object in motion stays in motion unless acted on by an external force.

Example: A book remains at rest until you push it.

Newton’s Second Law

F = ma (Force equals mass times acceleration).

Example: A heavier object requires more force to accelerate.

Newton’s Third Law

Every action has an equal and opposite reaction.

Example: A rocket launches by pushing gas downward, and the gas pushes back upward.

Friction

Resistance between surfaces (static & kinetic).

Example: Rubbing hands together generates heat due to friction.

Centripetal Acceleration

Acceleration toward the center of a circular path.

Example: A car turning on a curved road experiences centripetal acceleration.

Newton’s Law of Universal Gravitation

F = G(m₁m₂)/R², where G is the gravitational constant.

Example: The force between Earth and the Moon keeps the Moon in orbit.

Work

Force applied over a distance.

Example: Lifting a box onto a shelf requires work.

Kinetic Energy

Energy of motion (KE = ½mv²).

Example: A moving car has kinetic energy.

Conservation of Energy

Total energy remains constant.

Example: Roller coasters convert potential energy to kinetic energy and back.

Momentum

Mass times velocity (p = mv).

Example: A fast-moving truck has more momentum than a slow-moving car.

Impulse

Change in momentum (Impulse = Force × Time).

Example: Airbags reduce force by increasing impact time.

Torque

Rotational force.

Example: Using a wrench applies torque to loosen a bolt.

Angular Velocity

Rate of rotational change.

Example: A spinning bicycle wheel has angular velocity.

Period

Time for one cycle.

Example: A pendulum takes one second per swing.

Hooke’s Law

F = -kx (Force in a spring).

Example: Stretching a rubber band follows Hooke’s Law.

Voltage

Electric potential difference.

Example: A battery supplies voltage in a circuit.

Ohm’s Law

V = IR (Voltage = Current × Resistance).

Example: A high-resistance wire limits current flow.

Frequency

Number of waves per second.

Example: Radio stations broadcast at different frequencies.

Doppler Effect

Change in frequency due to motion.

Example: An ambulance siren sounds higher-pitched when approaching.