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Heat and its unit

Heat :- It is a form of energy. Heat energy can be transformed into  other forms of energies. Heat flows from a hotter body to a colder body.  Units of heat:- Calorie :- It is the quantity of heat required to raise the temperature of 1 gram of water through 1°C. Kilo calorie :- It is the quantity of heat required to raise the temperature of 1 kilo gram of water through 1°C. 1 kilo calorie = 1000 calories B.Th.U:-   It is the quantity of heat required to raise 1 lb of water through 1°F. (British thermal unit). 1 B.Th.U= 252 calorie C.H.U :-  It is the quantity of heat required to raise 1 lb of water through 1°C.( centigrade heat unit). Joule : S.I. Unit (1 Calorie = 4.186 joule) 1C.H.U = 453.6 calorie 1 C.HC. = 9/5 B.Th.U               = 1.8 B.Th.U Calorimeter :- The instrument used to measure heat is called calorimeter. Effects of heat:- • Change in temperature • Change in size • Change in state • Change...

Energy and their types

Energy :- The ability do work is called energy. Forms of energy in physical form:- 1. Mechanical energy  2. Electrical energy  3. Heat energy  4. Light Energy  5. Sound Energy  6. Chemical energy  7. Magnetic energy  Types of energy :- 1. Kinetic energy :-                                      The energy generated due to motion in an object is called kinetic energy.  K. E. =1/2 mv^2                m=mass           = 1/2 ×  w/g × v^2    v= velocity               g= gravitational acceleration                                                 (w=mg)  2. Potential energy :- T  he energy g...

Horse power types

Type of horse power :- 1.Indicated horse power(I. H. P)  :-   It is the power that is produced inside the cylinder or motor of an engine, it is also called theoretical horsepower. 2. Brake horse power(B. H. P)  :- This is the power we actually get from the engine.    3. Frictional horse power (F. H. P) :- The power lost due to friction is called friction horse power. I. H. P = PLAN   (in metric system)                  4500  P = average pressure in kg/cm^2 L = length of stroke in metre A =area of piston or cylinder in cm^2 N = r.p.m of crank shaft   I. H. P = PLAN (in British system)                   3000 In four stroke engine take r.p.m  =N/2 In double acting engine take r.p.m = N×2 In multi cylinder engine= I.H.P×No.of cylinder                 I. H. P = B. H. P +F. H. P B. H. P =I. H...

power and time

https://bulletprofitsmartlink.com/smart-link/66592/4   Power :-It is the work done in unit time. Power (p) = T otal workdone                          Total Time The SI unit of power is  = 1Nm/sec = 1joule /sec Which is equal to 1 Watt. Power in watts = w/t = F.s/t = F x V In M.K.S. system the unit is 1 kgf meter/sec.                                             One horse  power is = 75 kg metre/sec or 4500 kgf metre/min. 1HP (metric) = 735.5 Watts 1HP (British) = 746 Watts = 0.746 KW 1 KW = 1.34 HP Power input is the power given to a machine to do work. Power output is what we get out of the machine.  Power output is always less than power input due to friction in the machine.   The ratio between power output to power input is efficiency of the machine an...

work and energy

https://bulletprofitsmartlink.com/smart-link/66592/4   Work power and energy  Work is said to be done by a force, when it moves, its point of application through a distance. Applied force ‘F’ moves a body through a distance’s.           Work done ‘W’ = F x s. The S.I. unit of work is 1 joule which is the work done by a force of moving the body through a distance of 1 metre. Therefore M.K.S System   joule = 1 N x 1 metre = 1 Nm C.G.S System  Also 1 joule = 1 Nm = 10^5 dynes x 100 cm = 10^7 dynes cm=10^7 erg. F. P. S system    1foot pondal = 1foot x 1pound