Science flahscards week 9 Flashcards
What is Force?
push or pull; described by
strength.
What is a unit of force?
Newton (N); where 1N = 100 g
What is force instrument?
force meter/spring scale (N)
What is Net forces?
Combining Forces.
What does Unbalanced Forces equal?
mass
What does Balanced Forces equal?
No motion
What happens if two unbalanced forces are in the same direction?
The net force is the sum (+) of the
forces.
What is Friction?
The force that two surfaces exert
on each other when they rub against each
other.
What Factors Affect Friction?
weight, rough versus smooth surfaces ,lubricants (oils, grease); ball bearing and surface area.
What is static friction?
friction that acts on objects that
are not moving.
What is Sliding Friction?
friction when two surfaces slide
over each other.
What is Rolling Friction?
friction when an object rolls
across a surface.
What is fluid friction?
Friction when an object moves
through a fluid.
How is Friction Helpful?
STOP, MOVE, WARMTH, FIRE
How is friction Harmful?
WEAR OUT PARTS,FIRE (reentry from space),REDUCES EFFICIENCY.
What is Gravity?
An attractive force between
objects containing mass.
What Factors affect gravity?
Mass and Distance.
What is Mass?
amount of matter (atoms) in an object
What is Distance?
length between two points
What is terminal Velocity?
maximum velocity of a free falling object occurs when the force of air resistance equals the weight of the object.
What is weight?
The gravitational force exerted on an
object’s mass.
What is Free Fall?
only gravity acting on a falling object.
What is Air Resistance?
is a type of fluid friction as an object
falls through the air.
What is Projectile?
an object that is thrown.
What is Inertia?
Is the tendency of an object to resist a
change in motion.
What Factors affect Inertia?
Mass
What is Newton’s 2nd Law of Motion?
acceleration depends on the object’s mass and the force acting on the object.
what is Newton’s 1st Law of Motion Inertia?
an object at rest will remain at rest and an
object moving at a constant velocity will
continue moving at a constant velocity.
what is Newton’s 3rd Law of Motion Action/Reaction?
For every action there is an equal but opposite reaction.
What is momentum?
a measure (quantity) of motion, where:
