Strength or energy exerted or brought to bear
Force
The force that attracts a body towards the center of the earth
Gravity
A property of matter by which it continues in its existing state of rest or uniform motion in a straight line, unless that state is changed by an external force
Intertia
The resistance that one surface or object encounters when moving over another
Friction
A type of physical interaction that occurs between electrically charged particles
Electromagnetic force
A kind of friction that occurs between air and another object
Air Resistance
Momentum
A force that keeps an object at rest
Static Friction
A fundamental interaction that confines quarks into proton, neutron, and other hadron particles
Strong Nuclear force
The maximum velocity attainable by an object as it falls
Terminal Velocity
The law that states the amount of momentum remains constant; momentum is neither created nor destroyed, but only changed through the action of forces as described by Newton's laws of motion
Law of Conservation of Momentum
The resistance created by any two objects when sliding against each other
Sliding Friction
A fundamental force of nature that underlies some forms of radioactivity, governs the decay of unstable subatomic particles such as mesons, and initiates the nuclear fusion reaction that fuels the Sun
Weak Nuclear force
How much motion a specific object inherits after being propelled in a certain direction
Projectile motion
Mass
Occurs when a wheel, ball, or cylinder rolls freely over a surface
Rolling Friction
A force that pulls objects with mass toward each other
Gravitational force
The SI unit of force
Newton
The vector sum of forces acting on a particle or object
Net force
Something's relative mass or the quantity of matter contained by it
Occurs between fluid layers that are moving relative to each other
Fluid Friction
A force that acts on a body moving in a circular path and is directed toward the center around which the body is moving
Centripetal force