Energy Flashcards
State the conservation of energy
Energy cannot be created or destroyed. It can only be changed from one form into another.
Forms of energy
Kinetic Heat Chemical Potential Light Nucleur Electrical Sound
What is the most common type of wasted energy?
Heat energy
Gravitational field strength
The gravitational field strength is the force of gravity acting on 1kg of mass.
What happens when the force of friction acts?
When the force of friction acts, kinetic energy is converted into heat energy. Heat is often a wasted form of energy.
Work done formula (object moved horizontally by a force)
Ew = Fd
Ew = work done (J) F = force (N) d = distance (metres)
Potential energy formula
Ep = mgh
Ep = potential energy (J) m = mass (kg) g = gravitational field strength (9.8 Nkg-¹) h = vertical height (metres)
Kinetic energy formula
Ek = 1/2 mv²
Ek = kinetic energy (J) m = mass (kg) v² = speed (ms-¹)
Formula for falling objects
Ek gained = Ep lost
1/2 mv² = mgh
(Mass cancels out)
(Assuming no energy lost to heat due to air resistance)