PHYS 183 Lecture Notes - Lecture 3: World Energy Consumption, Nuclear Fusion, Chemical Energy

• School: McGill University
• Department: Physics
• Course: PHYS 183
• Professor: Gilbert Holder

Document Summary

Why is the sun bright: nuclear fusion: why the sun is so long lived, because it"s really big and hot. Sun has 99. 9% of mass in solar system. 1 watt (w) = 1 joule per second (j/s: joule is a unit of energy, dropping 1 kg of weight a distance of 1 m on earth"s surface produces. 1 w of energy: watt is power energy is used or emitted per second, continually dropping 1 kg (e. g) 1l of water) 1 m every second gives. Energy emitted by sun in 1 second is 4x10^26 j. World energy consumption in 1 year is 5x10&20j (1 millionth) How to generate energy: chemical energy (burning, burning 1 kg of gasoline releases 40x10^6 joules, if the sun were made of gasoline, burning the entire sun would release. Kelvin helmholtz contraction as eenergy source: gravitational energy slide 12. The sun has a huge amount of gravitational potential energy.