transverse and lonitudinal waves

physics- waves                                                                                                                 06/04/21 tansverse and longitudinal waves  Waves transfer energy from one place to another without transerring any matter( stuff). when waves travel through a medium, the particles  of the medium osillate ( move or siwing in  a rhythm) and transfer energy between each other. BUT overall, the particles stay in the same place- only energy is transfered  example: if you drop a twig into a calm pool of water, ripples form on the water's surface. the ripples dont carry the water( or the twing ) away with them through.  similarly,  if you strum a guitar string and create sound waves, the sound waves dont carry the air away from the guitar and create a vacuum. the formula for period:          T=1/F                                T= PERIOD(s)                 uinit of wave period is :s F= FREQUENCY(hz)    

traseverse waves have sideways vibration.                                                                          07/04/21          in transverse  waves, the oscillations (vibrations)  are perpendicular (at 90) to the direction of energy transfer. Most waves are transverse, including:     all electromagnetic waves e.g. light  ripples and waves in water  a wave on a string  longitudinal waves have parallel vibrations       in longitudinal waves, the oscillations are parallel to the direction of the energy transfer. an example is sound waves in air. waves speed = frequency * wavelenght  the wave speed is the speed at which energy is being transferred ( or the speed the wave is moving at). the wave equation applies to all waves:                                                             wave speed(m/s)= frequency(Hz) * wavelenght(m) 

Bio-fuels and Non-renewables

 bio-fuels are made from plants and waste                                                                       08/04/21 1) bio -fuels are renewable enregy resources created from either plant product or animal dung. they can be solid, liquid or gas an can be burnt to produce electricity or run cars in the same way as fossil fuels. 2) they are supposedly carbon neutral. bio fuels are fairly reliable. as crops take a relativelt short time to grow and different crops can be grown all year round,  however they cannot respond to immediate energy demands. the cost to refine bio fuels is very high. Non-Renewables are reliable... fossil fuels and nuclear energy are reliable, there is enough fossil and nuclear fuels to meet current demand, and the are extracted from the eart at a fast enough rate that power plants always have fuels in stock . this means that power plants can react quickly to change in demand. ... but create environmental problems coal, oil and gas release CO2  into the atmosphere when they're  burned. all this CO2 add to the green house effect, and contributes to global warming. burning coal and oil also releases sulferic dioxide, which causes acid rain- which can be harmful to trees and soils and can have far- reaching effects in ecosystems.  nuclear power is clean but the nuclear waste is very dangerous and difficuilt to dispose of.  

wind, solar and geothermal

Rewnebale  energy resources, like wind, solar and geothermal resources,                     09/04/21 will not run out,they don't generate as much electricity as non-renewable though. wind power- lots of little wind turbines  this involves putting lots of wind turbines up in exposed like on moors or coasts. each turbine has a generator, the rotating blades turn the genterator and produce electricity.  theres no pollution( except for a little bit when they're manufactured). you need about 1500 wind turbines to replace ne coal-fired power station and 1500 of them, cover a lot of ground- which would have a big effect on the scenery. very noisy problems of the turbines stopping en the wind stops or if the wind is too strong, and its impossible to increase supply when thers extra demand. on average wind turbines sproduce 70-8% of the time . the initial costs are quite high, but there are no fuel costs and minimal running costs solar cells- expensive but no environmental damage  solar cells generate electric currents directly from the sunlight. solar cells are often the best source of energy to charge batteries in calculators and watches which dont use much electricity. solar pannel are often used in remote places where there's not much choice. it can  power electric road signs and satalites. theres no pollution  solar power is very reliable in sunny countries but only in the day time.solar power can still be cost-effective even in cloudy countries like britian.  you cant increase the power output when ther is extra demand. initial costs are high but after the energy is free and running costs almost nil. solar cells are usually used to generate electricity on a relatively small scale.  geothermal power- energy in underground ermal energy stores  this is possible in volcanic area or where hot rocks lie quite near to the surface. the source of much of the energy is the slow decay of various radioactive elements, including ranium, deep inside the earth. brilliant free energy that's reliable and does very little damage to the environment. geothermal power can be used  to generate electricitity , or to heat buildings directly.  the main drawbacks with geothermal power are that ther aren't very many suitable locations for power plants and the cost of uilding a power plant is very high ompared to the amount of energy produces.