Essentially a machine is any devive by means of which a force applied at one point may be used to overcome a force at some other point.

Essentially a machine is any devive by means of which a force applied at one point
may be used to overcome a force at some other point.
Velocity ratio
The ratio of the distance moved by the effort to the distance moved by the load in the
same time is called the velocity ratio of the machine.
Efficiency
tts the raton of the useful work done by the iTachine to the total work put into the m
machine.
Density
Density is defined as mass per unit volume.
Relative density
The relative density of a substance is tin ratio. of the mass of any volume of the
substance of it to the mass of an equal volume of water.
Pressure
The SI unit of pressure is Newton metre -2.
Archimedes primciple
When a body is wholly or partillly immersed in a fluid it experiances anupthrust
equal to the weight of the fluid displaced.
A floating body displaces its own weight of the fluid in which it floats.
Temperature
The tempersture of a substance is a number which expresses it s degree of hotness on a
chosen scale.
Upper fixed point
The upper fixed point issteam from water boiling under standard atmospheric pressure
of 760mmhg.
Lower fixed point
The lower fixed point is the temperature of pur melting ice.
Coefficient of linearexpansion
The coefficient of linear expansion id the fraction of origianl length by which a rod
of the substance expands per degree rise in temperature.
Boyles law
The volume of a fixed mass of gas is inversely proportional to the pressure providing
the temperature remains constant.
Charles Law
The volume of a fixed mass of gas at constant pressure is proportional to its
absolute temperature.
pressure Law
The pressure of a fixed mas