Force
Force
a push or pull one body exerts on another
Law of Universal Gravitation
attractive force between two objects that depends on mass and distance between objects
Rolling Friction
The force between a rolling object and the surface it rolls on.
Newton's first law
An object will move at a constant velocity until an unbalanced force acts on it (might be ZERO)
*An object at rest stays at rest
*An object in motion stays in motion
Net Force
sum of all of the forces that are acting on an object
Weight
force that depends on gravity; gravitational force exerted on an object. W = F = ma = m(9.8)
Static Friction
The force that keeps an object at rest. The friction force is greater than the push or pull
Static Friction = force between two surfaces that are not moving past each other
Newton's second law
A net force action on an object causes the object to accelerate in the direction of the net force.
Inertia
the tendency of an object to resist a change in its motion. Inertia depends on mass. Increase mass, Increase inertia
Law of Conservation of Momentum
momentum is not gained or lost during a collision – it is transferred.
Fluid Friction
The force between an object and the medium, it is passing through (water, air, etc)
Newton's 3rd Law
Every action has an equal and opposite reaction, WHen one object exerts a force on a second object, that second object exerts a force back that's equal in size and opposite in directions
Friction
a force that resists a change in motion caused by two objects in contact with one another
Terminal Velocity
The maximum velocity a falling object can accelerate to. It occurs when the force of gravity equals the force of air resistance. It's 118mph for a person
Friction
Resistance to motion when two objects are in contact with each other
3 Factors that affect Friction
The roughness of the surface. Rough surfaces have greater friction because of microscopic bumps called microwelds
The force pushing them together. As a force like gravity pushes together, the microweldsThe gets more "hung up" on each other.
The amount of surface area touching the greater the surface area, the greater the friction.
force that opposes the motion of objects that move through the air. Caused by size, shape, and speed
Gravity
The attraction two objects have on one another. Large masses pull objects toward them, causing acceleration
Sliding Friction
The force between two surfaces sliding past one another
Sliding Friction = force that opposes the motion of two surfaces sliding past each other
Factors of Air resistance
More speed means more air resistance
The greater the size, the more air resistance
The greater perpendicular surface, the Morea it resistance