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Pascal’s principle
The pression exerted on the surface of a liquid is transmitted without changes in all the liquid.
The law states that given a fluid of constant density, the pressure exerted by a column of fluid in a point of its depth h is directly proportional to h,
P= d*g*h
being the acceleration of gravity g = 9.8 m / s ².
d= P/h*g
h= P/d*g

Archimedes’ principle
When a body is wholly or partly immersed in a fluid it experiences a upward force (upthrust) equal to the weight of the fluid displaced.
With reference to the density of an object we can say that:
1. If the density of the fluid is greater than or equal than the density of the object, the object floats
2. If the density of the fluid is lower than the density of the object, the object sinks.
States of Matter
Plasma (ionized gas at a very high temperature)

changes of state
Solid Liquid = FUSION
Liquid  Gas = VAPORATION
To change its states matter must lose or gain energy in the form of heat
The energy needed per unit of mass is called the latent heat
To measure the quantity of energy we need to change the state we have to multiply the latent heat of that substance for the mass we have, this in case the object is already at its temperature.
E=m*L m=mass; L= latent heat
During this process remember that the temperature remains constant.
If the substance is not at its critical temperature, we must reach that temperature to allow the beginning of the change of state.
The energy we need to reach is the critical temperature; it can be calculated using this formula:
Q= E = m*c*Δt c= specific heat capacity; Δt= difference between final and initial temperature
Δt= Q/m*c
m= Q/c* Δt
m= Q/c* Δt  J/ (J/Kg*K°)K°= Kg

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