1) Electrical energy --> whenever a current flows
2) Light energy --> from the Sun, light bulbs.
3) Sound energy --> from loudspeakers to anything noisy
4) Kinetic energy --> anything that moves
5) Nuclear --> released only from nuclear reactions
6) Thermal energy --> flows from hot objects
7) Gravitational potential energy --> possessed by anything that can fall
8) Elastic potential energy --> possessed by springs, elastic
9) Chemical energy --> possessed by foods, fuels, batteries
ENERGY CONSERVATION: This is about using fewer resources because of the damage it is doing to the world and they might run out one day.
THE PRINCIPLE OF THE CONSERVATION OF ENERGY: It's an all-pervading principle which governs the working of entrie physical universe. It is stated as:
"ENERGY CAN NEVER BE CREATED NOR DESTROYED. IT'S ONLY CONVERTED FROM ONE FORM TO ANOTHER."
Efficiency = USEFUL ENERGY OUTPUT / TOTAL ENERGY INPUT
"An ordinary lightbulb is 5% efficient. If 1000 J of light energy is given out, how much is energy wasted?"
1000 J / 0.05 = 20,000 J
20,000 - 1000 = 19,000 J
Gravitational Potential Energy
GPE = mass x gravitational field strength x height
m x g (10) x h
"On Earth, a ball of mass 0.5kg is kicked straight up. How much GPE does it have at its highest point 6m off the ground?"
0.5 x 10 x 6 = 30 J
Moon = 1.6N/ kg
Jupiter = 26N/ kg
KE = 1/2 mv²
KE = 1/2 x m x v²
KE = Joules
M = Kilograms
V = m/s
What is the kinetic energy of a 1000 kg car travelling at 5 m/s?
1/2 x 1000 x 25 = 12,500J --> The 5 is squared, therefore it is 25.