Study Guide Flashcards
What is a reference point?
a place or object used for comparison to determine whether an object is in motion.
What is motion?
An object is in motion when its distance from another object is changing.
What is speed?
the distance an object travels in one unit of time.
What is velocity?
Speed in a given direction.
What is the International System of Units (SI)?
a system of measurement based on multiples of ten and on established measures of mass, length, and time.
What is a meter?
the basic SI unit of length.
Acceleration-
the rate at which velocity changes.
Force-
A push or a pull exerted on an object.
Net Force-
the overall force on an object when all individual forces’ actions are combined.
Newton(N)-
a unit of measurement that equals the force required to accelerate one kilogram of mass at one meter per second per second (1m/s2).
Balanced Forces-
equal forces acting on an object in opposite directions.
Mass-
the amount of matter in an object.
Newton’s First Law of Motion-
An object at rest will remain at rest and an object that is moving at a constant speed will remain moving at a constant speed unless acted upon by an unbalanced force.
Friction-
the force that one surface exerts on another when the two rub against each other.
Sliding Friction-
when solid surfaces slide over each other.
rolling friction-
when an object rolls over a surface.
Fluid Friction-
the friction that occurs when an object moves through a fluid.
Strength of frictional force-
depends on the types of surfaces involved and how hard the surfaces are pushed together.
Direction of Frictional Force-
depends on the way the object is being pushed or pulled.
Gravity
The force that pulls objects towards Earth.
Free Fall-
The motion of a falling object when the only force acting upon it is gravity.
Air resistance-
The fluid friction experienced by objects falling through air.
Weight-
The force of gravity on an object at the surface of the planet.
Why are reference points needed?
Reference points are needed to be able to see an object in motion.