Chapter 2: The Laws of motion Flashcards
Force
A push or pull
Newton
The metric or SI unit for force
Net force
the combination of all forces acting on an object
Friction
The force that two surfaces exert on each other when they rub against each other
Gravity
A force that pulls objects towards each other
Law of Universal Gravitation
The force of gravity that acts between all objects in the universe
Mass
The amount of matter in an object and is measured in kilograms.
Free fall
When gravity is the only force acting on an object
Air resistance
A force that opposes objects moving through the air
Terminal Velocity
The point where the force of gravity is equal to the force of air resistance on an object
Projectile motion
The curved path an object follows when it is thrown or propelled near the earth
Inertia
The tendency of all objects to resist a change in motion
Momentum
The product of the mass and velocity of an object
Law of conservation of Momentum
As long as there are no outside forces the momentum of a group of objects will be the same before and after they collide
Calculate net force when forces are ; same direction, opposite direction, equal force
Different - add all the forces, greater number is positive and the lesser is negative when adding.
Same - Add all forces
Equal - will always equal 0
What is a balanced force
Equal forces acting on an object in opposite directions.
What are the two things that effect friction on an object?
- How hard the surfaces push together
- The types of surfaces involved
four types of friction with an example of each
Static (paper on a table)
Sliding (rubbing hands together)
Rolling (skateboarding)
Fluid (surfing)
What did Sir Isaac Newton contribute?
realized gravity was in effect on Earth and everywhere else in the Universe
What famous book did Sir Isaac Newton write?
Principia (Philosophae Naturalis Principia Mathematica)
What are the two factors that affect gravity?
Mass and Distance
What is the constant gravity on Earth?
9.8
What is the difference between mass and weight?
Mass is the amount of matter in an object while weight is the amount of gravitational force exerted on an object.
formula to calculate the velocity of an object under gravity’s influence.
Velocity = Gravity x Time
Newtons three laws of Motion
- an object will not change its motion unless a force acts on it. 2. the force on an object is equal to its mass times its acceleration. 3. when two objects interact, they apply forces to each other of equal magnitude and opposite direction.
What is the relationship between acceleration and force?
Acceleration and force will always occur in the same direction
What is the relationship between acceleration and mass.
inverse - Acceleration decreases as mass increases
What are force pairs?
all forces act in pairs the result is a net force of zero
Formula to calculate the momentum of an object.
Mass x Velocity
calculate force
Mass x Acceleration
