AP Physics 1 Unit 2 - Dynamics: Basic Principles

An object at rest will remain at rest, and an object in motion will remain in motion unless acted upon by a net unbalanced force (acceleration).

The net force of an object equals the mass times acceleration of the object. The acceleration of the object is also directly proportional to the net force applied, and inversely proportional to the objects mass.

For every action, there is an equal and opposite reaction. If object A exerts a force on object B, then object B must exert a force of equal magnitude and opposite direction back on object A.

The tendency of an object to resist changes in its motion, whether it is at rest or in motion. It is a property of matter.

An object is in static equilibrium when it is at rest and the net force is zero

An object is in dynamic equilibrium when it is moving at constant velocity and the net external force is zero

The vector sum of all forces acting on an object (remember vector addition)

The same as the direction of acceleration. (As shown by the vectors in Newton’s second law of motion equation)

The net force of an object is directly proportional to the acceleration of an object, as shown by in Newton’s second law of motion equation). For example, if the net force of an object is doubled and the mass remains constant, the acceleration is also doubled.

The object with the lesser mass has the greater acceleration because acceleration is inversely proportional to mass.

The net force acting on the object

The acceleration is halved because acceleration is inversely proportional to the mass of the object.

The objects motion could be at rest or moving with constant velocity.

It is equal to the weight of the object, as because the weight of an object = the net force of an object = the mass of the object * the local gravity (g).

There is no net force acting on the object.

There is a larger force acting on a small mass, because of the equation acceleration = net force/mass, so a greater numerator over denominator is a bigger number.

The acceleration remains the same, because of the equation acceleration = net force/mass, if both the net force and mass are tripled, the 3’s cancel out.

Both the net force on the object and the mass of the object.

Every particle attracts every other particle in the universe with a force that is proportional to the product of their masses and inversely proportional to the square of the distance between their centers.

The gravitational force on the object.

The weight of an object = the mass of the object * the acceleration due to gravity.

It is (meters/seconds²) or (Newtons/kilograms).

The acceleration that a free-falling object would experience due to gravity.

The center of the planet.

Mass is the measure of matter, and weight is a measure of gravitational force.

9.81 meters per second²

The weight of an object is directly proportional to the gravitational field strength. This is proved using the equation for weight, weight = mass * gravity. Taking the proportionality of weight and gravity, we see that weight is directly proportional to the gravitational field strength.

Equal to the gravitational field strength (g).

It gives rise to the force that we measure as the object’s weight.

g varies depending on the mass of the planet and the distance from its center, while G is a universal constant.

They are equal in magnitude and opposite in direction.

They are part of a force pair and act on different objects in opposite directions.

The interactions between all objects, regardless of their size.