Topic 1: Energy Flashcards
What are the eight forms of energy?
Thermal, Kinetic, Gravitational Potential, Elastic Potential, Chemical, Magnetic, Electrostatic, Nuclear.
What is the calculation for Work Done?
WORK DONE = FORCE x DISTANCE
W = F x D
Joules = Newtons x Metres
Define Work Done.
Work done is the product of the force and the distance over which the force is applied.
What is the calculation for Weight?
WEIGHT = MASS x GRAVITATIONAL FIELD STRENGTH W = m x g Newtons = Kilograms x Newtons per Kilogram
What is the calculation for Gravitational Potential Energy (GPE)?
GRAVITATIONAL POTENTIAL ENERGY = MASS x GRAVITATIONAL FIELD STRENGTH x HEIGHT
Ep = m x g x h
Joules = Kilograms x Newtons per Kilogram x Metres
What is the calculation for Elastic Potential Energy?
ELASTIC POTENTIAL ENERGY = 1/2 x SPRING CONSTANT x (EXTENSION)^2
Ee = 1/2k x e^2
Joules = Newtons per Metre x Metres^2
What is the calculation for Kinetic Energy?
KINETIC ENERGY = 1/2 x MASS x (SPEED)^2
Ek = 1/2m x (v)^2
Joules = Kilograms x Metres per Second^2
What is the calculation for Efficiency?
EFFICIENCY = USEFUL ENERGY TRANSFERRED
———————————————–
TOTAL ENERGY SUPPLIED
Can an energy transfer be more than 100% efficient?
No, no energy transfer can be more than 100% efficient.§
Why do machines waste energy?
Machines waste energy because of friction between their moving parts, air resistance, electrical resistance, and noise.
What is the equation for power?
POWER = WORK DONE
———————
TIME
Watts = Joules / Seconds
What is another equation for power?
POWER = ENERGY TRANSFERRED
————————————
TIME
Watts = Joules / Seconds
One Watt =?
One Watt = 1 joule of energy transferred per second.
What is the Conservation of Energy Principle?
Energy can be transferred usefully, stored or dissipated, but can never be created or destroyed.
Define Power
Power is the rate of energy transfer or the rate of doing work.