Physics: Forces, Gravity, Magnetism, and Electrostatics

Vocabulary flashcards covering the concepts of contact and non-contact forces, mass, weight calculations, magnetic fields, magnetic materials, electrostatics, conductors, and lightning.

Force

A push or a pull exerted on an object, measured in Newtons ($\text{N}$), that acts in pairs that are equal in size and opposite in direction.

Newton ($\text{N}$)

The standard unit of measurement for force.

Contact Force

A force that results when two objects are in direct physical contact or touching, such as tension, compression, and friction.

Non-Contact Force

A force that results from action at a distance between objects without physical contact, such as gravity, magnetic force, and electrostatic force.

Friction

The contact force that acts between two objects or surfaces rubbing together, such as sandpaper rubbed on wood or hands rubbing together.

Tension

The contact force that acts when an object is pulled or stretched, such as pulling a rope or stretching a rubber band.

Compression Force

A contact force that pushes or squashes matter together, such as pressing an air freshener into a container.

Gravitational Force

The non-contact field force that pulls matter together, exerted by all objects on other objects around them.

Mass

The amount of matter contained in an object, measured in kilograms ($\text{kg}$), which remains constant regardless of location.

Weight

The gravitational force exerted on an object by the Earth, measured in Newtons ($\text{N}$), which varies depending on the gravitational force.

Gravitational Acceleration ($g$)

The acceleration imparted to objects by gravity on Earth, defined as $9.8\,\text{m/s}^2$.

Weight Formula

The mathematical formula $W = m \times g$, where $W$ is weight in Newtons ($\text{N}$), $m$ is mass in kilograms ($\text{kg}$), and $g$ is gravitational acceleration ($9.8\,\text{m/s}^2$).

Magnetic Field

The space surrounding a magnet where a magnetic material experiences a magnetic force.

Magnetic Field Lines

Continuous lines representing a magnetic field that start at the North Pole and end at the South Pole, never touch or cross, and are drawn closer together to indicate stronger force and further apart for weaker force.

Magnetic Metals

Metals that are attracted to magnets, specifically iron, nickel, and cobalt.

Magnetic Shielding

The phenomenon where magnetic forces pass through non-magnetic materials but cannot penetrate magnetic materials, utilized in metal casings to protect sensitive instruments like watches.

Electrostatic Charge

Electric charges that are at rest and not moving.

Proton

A positively charged subatomic particle located inside the nucleus that does not move during charging.

Electron

A negatively charged subatomic particle that can transfer from one substance to another when friction or rubbing provides energy.

Law of Electrostatic Charges

The physical rule stating that like charges repel ($+\text{ and }+$ or $-\text{ and }-$) and opposite charges attract ($+\text{ and }-$).

Conductors

Materials that allow electric charges to move through them easily, such as copper and gold.

Lightning

A rapid electrostatic discharge occurring when friction between strong air currents and ice particles in storm clouds charges particles, causing built-up charge to jump between clouds or to Earth.

Thunder

Sound shock waves created when the quick flow of electrical charge during lightning rapidly heats the surrounding air.