AP Physics 1 Set 3

newton’s first law

an object will continue in its state of motion unless to change by a new force impressed upon it

inertia

the property of an object that describes its natural resistance to changes in their state of motion. Ti is equivalent to its mass

law of inertia

also known as newton’s first law

newton’s second law

predicts what will happen when an unbalanced force does act on an object: the object’s velocity will change; the abject will accelerate according to Fnet

newton (N)

a force of 1kg . m/s² is renamed as 1 newton

newton’s third law

states that the force from object 2 on object 1 is equal in magnitude but opposite in direction to the force from object 1 on object 2

action/reaction pair

to every action, there is an equal, but opposite, reaction. If object 1 exerts a force on object 2, then object 2 exerts a force back on object 1, equal in strength but opposite in direction. These two forced are called an action/reaction pair

weight

the gravitational force exerted on it by Earth (or whatever planet it is on)

mass

measure of the quantity of matter that comprises an object. It is equivalent to its inertia

normal force

when an object is in contact with a surface, the surface exerts a contact force on the object. Component of the contact force that is perpendicular to the surface

free-body (or force) diagram

a diagram with the object represented as a dot and all the forces that act on the object as arrows connected to the dot

friction

when an object is in contact with a surface, the surface exerts a contact force on the object. Component of the contact force that is parallel to the surface

static friction

occurs when there is no relative motion between the object and the surface (no sliding)

kinetic (sliding) friction

occurs when there is relative motion (sliding)

coefficient of friction

the strength of the friction force depends on two things: nature of the surfaces and the strength of the normal force. The nature of the surfaces is represented by this, which is denoted by μ (mu) and has no units

pulleys

devices that change the direction of the tension force in the cords that slide over them. These systems multiply the force by however many strings are pulling on the object

inclined plane

a ramp. the force of gravity parallel to the ramp (downhill) is given by Fg.|| = mgsinθ, where θ is the angle of the inclined plane