The pressure p and the volume V of a gas are connected by the relation, 
, where k is a constant. Find the percentage increase in the pressure, corresponding to a diminution of 0.5% in the volume.
Given: pv1/4 = k
%decrease in the volume = 1/2%s
∴ 
pv1/4 = k
taking log on both sides
log[pv1/4] = log a
log P + 1.4logV = log a
Differentiating both the sides we get
⇒ 
⇒ 
Multiplying both sides by 100.
⇒ 
⇒ 
⇒ 
%error in P = 0.7%.
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