science final review - unit 6 forces and motion

collision

two or more objects come into contact and at least one of them is moving

damage

physical breaking or bending that results in a permanent shape change (takes effort/time to fix)

force

a push or a pull

newtons first law

an object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction at constant speed unless acted upon by a force. This principle explains the inertia of an object, indicating that external forces are required to change its state of motion.

acceleration

the rate at which the velocity (speed and/or direction) of an object changes.

*acceleration takes into account the change in speed and how long it takes to change.

is acceleration always positive?

no, any object that speeds up, slows down, or changes its direction is said to be accelerating

when an object is slowing down, we put a negative in front of the acceleration value

formula for acceleration

change in velocity/time (units are usually m/s², but this could change)

velocity

the speed AND direction of an object in motion

newtons third law

every action has an equal and opposite reaction This law explains how forces always occur in pairs, meaning that if an object exerts a force on another object, the second object exerts a force of equal strength in the opposite direction.

newtons second law

force = mass x acceleration. how much an object accelerates depends on its force and mass

net force

The overall force acting on an object when you combine all the individual forces.

It’s what determines whether an object will start moving, speed up, slow down, stop, or change direction.

motion graph with a horizontal line

indicates that an object is at rest. The slope of the line is zero, showing no change in position over time.

motion graph with a straight line upwards

shows that object is traveling at a constant speed - important to note that its NOT accelerating since it is constant

motion graph with an inconsistent slope

shows that object is either accelerating or decelerating (look at direction of graph) - speed is not constant