Chapter 1 Energy Terms Power is the rate of energy release Energy is the ability to do work A Calorie is the amount of energy used to raise the temperature of 1 g of water by 1 celsius Kinetic Energy is the energy in moving things Potential Energy is stored energy for example a compressed spring Equations Power Energy Time Kinetic Energy Equation E 1 2 mv Energy Energy is the ability to do work Can be active Kinetic Moving or stored Potential Mechanical Electrical Chemical Energy is measured in Joules Calories Kilowatt Hours BTU s and Quads which are 10 15 BTU s year BTU s are usually used to measure the amount of energy the entire world uses per When the economy grown energy use grows and Vice versa For example in the 2008 recession less energy was made and less was used Energy is always conserved when it changes forms First Law of Thermodynamics An explosion occurs when a great deal of stored energy is suddenly converted to heat in a confined space Batteries have low energy but a high kWh cost Forms of Energy Kinetic Energy is the energy in moving things Potential Energy is stored energy for example a compressed spring Nuclear Energy is the energy stored in the bonds of atoms Gravitational Energy is the energy that an object has at an high altitude Chemical Energy is the energy stored in the forces between atoms Heat is all forms of energy Kinetic Energy Kinetic Energy Equation E 1 2 mv 2 1 meter per second mps 2 miles per hour mph 1 kilogram kg 2 pounds lb Power Power is the rate of energy transfer Power plants just convert energy they never actually create it Energy cannot be created About 2 3rds of a power plants energy is lost in heat The brightness of a light build depends on how much power it uses 60 Watt bulbs 40 Watt bulbs etc Uranium The huge forces in the uranium atoms provide its high energy most atoms it is hard for this energy to be released but in uranium through chain reaction it is released very easily Coal Coal is dirt cheap Coal takes up less space and is less dense than gas Solar Panels The sun is a sustainable source of energy Solar panel power outputs 1 square meter of solar panel 1 kilowatt of sunlight 150 400 watts 1 square kilometer 1 gigawatt of sunlight 150 400 megawatts Smart Rocks A Smart Rock is a rock with a computer chip in it The rock will get in the way of missiles Used in ballistic missile defense From the missiles perspective the rock is coming at is very very fast Change in perspective is called classical relativity Things you may need Know Electric cars are pricer in the long run because of the cost of replacing the batteries Hybrid engines are very e cient they run on gasoline and electricity To recharge a fuel cell you give it more fuel while to recharge a battery you have to recharge it with electricity from elsewhere Electrolysis is when electricity is passed through water to produce hydrogen and oxygen 1 kilogram of hydrogen 1 gallon of gasoline energy wise Hydrogen is hard to store and transport and produces less energy than gas per area Hydrogen cannot be mined Book Quiz practice Questions
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