Chapter 5- Force and Motion I

Newton

Newton

a unit of force equal to the force that imparts an acceleration of 1 m/s^2 to a mass of 1 kilogram.

Newtonian mechanics

The system of mechanics which relies on Newton's laws of motion concerning the relations between forces acting and motions occurring.

Gravitational force

The force of attraction between all masses in the universe; especially the attraction of the earth's mass for bodies near its surface.

constant acceleration

Every body with a(n) ________ has a net force of zero.

Mass

The amount of substance in a body.

long distance

If a puck is slid over a slippery surface, it continues to move for a long time and covers a(n) ________.

Weight

The force with which a body is pulled toward the earth.

Newtonian mechanics

When the size of the object becomes extremely small (near the atoms size), ________ is replaced with quantum physics.

UNIT

The unit of force can be stated in terms of the acceleration a force would give to the standard kilogram

VECTORS

Since force has both, a unit and direction, it is a vector quantity

Using the ideas above, the first law of motion can be more clearly stated in terms of net force as

If no net force acts on a body, the bodys velocity cannot change; that is, the body cannot accelerate

Newton's First law of motion

It states that if there is no net force on a body, the body remains at rest if it is initially at rest or moves in a straight line at constant speed if it is in motion.

Newton's Second law of motion

It states that the net force is equal to the product of mass and acceleration of that object.

Newton's Third law of motion

It states that an object in equilibrium has an equal but opposite force acting upon it.

Inertial Reference Frames

Reference frames in which the Newtonian mechanics hold.

Normal force

The force on a body from a surface against which the body presses which is always perpendicular to the surface.

Frictional Force

The force that always opposes a body in motion.

Free body diagram

A stripped-down diagram in which only one body is considered.