thermodynamics 1st law??

   it states energy can neither be created nor be destroyed i.e. it remains conserved

 change in u= q + w 

u=internal energy

q= heat

w= wrk done by/on the system

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if we apply heat in a system it woks ifo two cases............................... one to change nits internal energy other t do work............  it follows the conservation of energy..................  it is the thermodynamics first law.......

if you like it please approve my answer...........

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