Properties Of Solids And Liquids Question 125
Question: Assertion : Pascal law is the working principle of a hydraulic lift. Reason : Pressure is equal to thrust per area.
Options:
A) If both assertion and reason are true and the reason is the correct explanation of the assertion.
B) If both assertion and reason are true but reason is not the correct explanation of the assertion.
C) If assertion is true but reason is false.
D) If the assertion and reason both are false.
E) If assertion is false but reason is true.
Show Answer
Answer:
Correct Answer: B
Solution:
According to Pascal’s law, if gravity effect is neglected, the pressure at every point of liquid in equilibrium of rest is same.
$ P _{1}=P _{2} $ i.e. $ \frac{F _{1}}{a _{1}}=\frac{F _{2}}{a _{2}} $
or $ F _{2}=\frac{a _{2}}{a _{1}}F _{1} $ As $ a _{2}»a _{1} $ $ F _{2}»F _{1} $
This shows that small force (F1) applied on the smaller piston (of area a1) will be appearing as a very large force on the larger piston.
