forces & motion

• Energy is the ability to move and cause change and cannot be created or destroyed.
• Force is a push or pull effect exerted on an object.
• Motion is the movement of an object from one place to another.
• An object is said to be in motion when its position changes continuously with respect to a stationary object taken as a reference.
• A reference point is an object that is used for comparison to determine whether something is in motion.
• Balanced force is when the force acts on an object is equal in strength and acts in opposite directions, resulting in net force being 0.
• Unbalanced force is when the force acts on an object is not equal in strength and acts in one direction, resulting in net force not being 0.
• Net force is the combination of all forces acting on an object.
• Speed is the distance an object travels over a unit of time, represented by the equation Speed = Distance/time.
• Velocity is the speed at which an object travels in a given direction, and velocity depends on both speed and direction.
• Acceleration is the rate in which an velocity changes, and can increase, decrease, or change in direction.
• Contact force is a force as a result of making contact with objects.
• Non-contact force is a force that isn’t a result of making contact with objects.
• Newton’s 2nd law of motion states that net force is equal to mass x acceleration, meaning the heavier the mass the less force.
• Newton’s 3rd law of motion states that for every action there is an equal and opposite reaction, meaning if object A exerts a force on object B, then object B must exert an equal force of opposite direction back on object A.