In this lesson our instructor talks about forces. First, she discusses force, friction, and Newton's Laws of Motion. Then she talks about gravitational force. Four complete example videos round up this lesson.
Balanced forces – balanced
forces means that the net force = zero
Unbalanced forces –
unbalanced forces on an object cause the object to move in the
direction of the larger force or the net force. Unbalanced forces
cause the acceleration of the object.
Friction – force that brings
objects to a stop.
Static Friction-two surfaces in
contact are prevented from sliding past one another – must
overcome this force to begin moving a stationary object.
Sliding Friction-brings a
sliding object to a stop due to contact of two surfaces.
Rolling Friction-force between
surface of wheel and surface that the object is rolling on.
Air Resistance – A frictional
force between air molecules and a falling object – the larger the
surface area of the falling object, the larger the force of the air
Fluid friction – force
between an object and a liquid.
First Law of Motion – an
object at rest will stay at rest and an object in motion will stay
in motion unless an outside force acts upon it.
Second Law of Motion –
acceleration of an object is in the same direction as the net force.
Third Law of Motion – for
every action force, there is an equal and opposite reaction force.
Lecture Slides are screen-captured images of important points in the lecture. Students can download and print out these lecture slide images to do practice problems as well as take notes while watching the lecture.