Energy, Power And Work And Force Flashcards
What is potential energy and how do you calculate it
Potential energy is the energy a body possesses because of its position or state
mgh
What is kinetic energy and how do you calculate it?
Kinetic energy is the energy a body possesses because of its motion
KE = 1/2 mv^2
How do you calculate the change from PE to KE
Find the potential energy and that = the kinetic energy so if the potential energy was 4000 it would be
KE = 4000
4000 = 1/2 mv^2
What is a force?
A push or pull measured in newtons
What is weight?
Downward pull of gravity on body
What is Tension
The force when an object is being stretched
What is friction?
A force that stops objects
What is Newton’s first law?
An object won’t change its motion unless a force acts on it
What is Newton’s second law?
The force on an object is equal to its mass times acceleration
What is Newton’s third law?
When two objects interact they apply forces to each other of equal but opposite direction
How do you calculate force?
Force = m x a if it is vertical
Force = m x g if it is horizontal
If gravity is not given it is 10
What is the mass of an object?
The amount of matter it contains
What is weight
The pull of a body caused by gravity
How do you calculate weight?
Weight = mass x gravity
What is a stable equilibrium?
It returns to its original position.
It is drawn as the bottom half of a semi circle with an object in the middle
What is neutral equilibrium?
When a body has no tendency to return to its original position or move further away.
What is and How do you draw unstable equilibrium?
An object that moves further away from its original position
You draw it with a top half of a semi circle and an object on top. If it’s a bottle it goes upside down
What is energy?
The capacity to perform work
What are the types of energy?
Heat, electrical, potential, kinetic, chemical, sound, nuclear, light, mechanical and magnetic.
Hey everyone Peter killed Carl and Sam near limegrove Monday morning
What are environmental friendly energy sources?
Solar, wind, geothermal energy and waves
What are energy converters?
When appliances change from one form to another
What are the energy’s used in a car
Chemical —> Mechanical —> Kinetic + Heat
What are the energy conversions in a lightbulb
Electrical —> Light + Heat
What are the energy conversions of a television?
Electrical —> light + sound + heat
What are the energy conversions of a tractor?
Chemical energy —> kinetic + sound + heat energy
What is the energy of photosynthesis?
Light —> chemical
What are 4 ways to conserve energy?
Turn off light when not being used, unplug appliances that are not being used, do not leave the fridge door open and energy efficient engines burn less fuel
What is the problem with fossil fuels?
A lot of money is spent on fossil fuels
What is work?
Work is done whenever an object is moved by force
How do you calculate work?
Work = force x distance
What is the unit of work?
Joule J
What is power?
Power is the rate of doing work
How do you calculate power
Power = work/time
What is the unit of power?
Watts W
How do you calculate the resultant force?
If there are two on the same side add them, if there are two on different sides take the largest away from the smallest and the largest is the direction your answer goes in, and if they are the same on both sides it is equal
What kind of Quantity is
Force?
A vector quantity
What a Vector quantity?
A quantity that has Magnitude
& Direction
