Fun with physics

Hey guys, It's chilling cold here in this part of the country.What about your country?Today I am going to discuss why Some countries employ 220volt and some 110volt for household consumption.Actually the choice dates back to history when Thomas Edison and his company gave electricity at 110volt DC.Since it was employed first so people had mindset of having 110volt as safe.Although Nikola Tesla suggeted for 220volt AC but it was rejected by people.Now European countries required high voltages for big machines during world war 2,so they started giving 220volt and is continued till date.India also has 220volt power supply for household.Japan has110 volt.Now the question is which one is safer and which one is economical.Well as far as safety is concerned 110volt is much safer than 220volt but 110volt is costlier.Because for 110volt supply the wire required should have greater area of cross section so that resistance is less.Since resistance is inversely proportional to area of cross ...

Hey guys, Hope all is well with you all.This post is for class 11th students and engineering students of civil and mechanical streams.In 11th std physics book the definition of stress is simply given as the force applied per unit area on a body.Mathematically it is all good.But as far as real definition according to mechanics is concerned it is the reacting force generated per unit area in response to the external force applied.Had it been not so you cannot define the maximum stress limit of an object.Whenever stress limit is exceeded the object attains fatigue and tends towards fracture.Meaning stress of any object is bearable response to external load.Take an example of our daily life where we say the work load in office has created much stress in my life.Here stress refers to the mental stress caused due to work pressure.Here our brain is responsing to external pressure.Both the cases are similar.So understand this anology.So for a good engineering student stress is the force acti...

Hii, Next revolution in the field of energy is renewable energy.All the major developed countries have already started implementing it.One of the major source of renewable energy is solar energy.But do you know how solar panels work?The physics behind it is divided into certain stages.Solar plates employ photovoltaic cells which convert light into electricity.As light is dual in nature meaning it has particle and wave nature.Here the particle nature comes into play.Particles are nothing but photons(small packets of energy).When the photons hit the photovoltaic cell charges flow from positive to negative terminals.This electricity is DC in nature which is converted to AC with the help of inverter consisting of capacitor.Thus electricity is provided at our household loads.The excess electricity is sent to grid which provides you electricity on cloudy days.Moreover if you can transfer more energy to grid by consuming less,the government gives you subsidy also in most countries.So I hope...

Hey, This post is for everyone.From childhood we have grown up seeing our parents giving water to plants using pipes.We all have tried our hands also in that.Now we have always heard that by reducing the pipe diameter by using our fingers blocking the outlet we can increase water pressure and water will go further distance.No doubt water will travel longer distance but in this case pressure is not increasing but velocity is.Dont get confused by the formula of pressure (F=M/A) as it is applicable for solids only.In case of liquids it will follow Bernoulli's  equation stating if area is decreased kinetic energy or velocity gradient will increase and pressure gradient will decrease.So now it should be clear to all. Thanks....

Hey Kids, This post is for standard 9th students.You must be having chapter of pressure in mechanics and as of now you must have become familiar with the terms scalar and vector.If a quantity can be defined completely using only magnitude it is scalar and if direction is also required apart from magnitude then it is vector.By the definition of pressure it is Force acting per unit area.Here what happens is that no matter where you apply the pressure,its effect will be taken by the perpendicular component of that force acting on unit area.Since here it is predefined that you should take only the perpendicular component so you don't have to worry about direction.Your books might not contain above facts as these are more precisely defined in 11th standard.For the time being just know that it is scalar as it force will be perpendicular to area.You will know about vector additions,multiplications,divisions and triangle rule in higher classes.Then it will become more clear. Thanks...

Hello friends, This one is a puzzle question.There were two bears A and B having same mass m.But weight of A being higher than B. Tell the colour of A and B. .... Confused... If two things have same mass but different weight then there must be difference in acceleration due to gravity.Now,due to oblate spheroidal shape of earth the radius of earth varies at poles and equator.The radius being smaller at poles,g will be higher since g=Gm/r2.Therefore the bear must be at North or south pole.Since polar bears are found in north pole,so the colour will be white.Hence A has white colour and B black. Thanks...

Hey guys, We all have heard about transformers and we also know that what does it do.Transformers have been created to transfer required voltage at required destination.It works on the principle of mutual induction.There are two types of transformers,one step up and other step down.Step up increases voltage and step down decreases voltage.As its use differs at different situations,so transformers are given units KVA or MVA but not in watt or kilowatt.Because transformers transfer power but they don't consume it.So it is not a load but it is a machine that supplies power to loads.The users of transformers will get to know from its unit that where they should use this according to the voltage required for the particular load.So remember transformers are not loads but they provide power to loads.The load can be house'sTv,Fridge,AC,cooler,Fan etc.Depending upon the type of loads transformers are used. Thanks...