Physics
Assertion (A) : A hydraulic jack is used for squeezing oil out of linseed and cotton seeds.
Reason (R) : It works on the Pascal's principle.
- both A and R are true and R is the correct explanation of A
- both A and R are true and R is not the correct explanation of A
- assertion is false but reason is true
- assertion is true but reason is false
Answer
both A and R are true and R is the correct explanation of A
Explanation
Assertion (A) is true because hydraulic jacks are commonly used in oil extraction processes to apply large pressure over a small area to squeeze oil from seeds.
Reason (R) is true because Pascal's principle states that :
“When pressure is applied to a confined fluid, it is transmitted equally in all directions throughout the fluid.”
This principle allows a small force applied on a small piston to produce a large force on a larger piston, making the jack effective for pressing operations like oil extraction, since the hydraulic jack works because of Pascal’s principle, the Reason correctly explains the Assertion.
Related Questions
What force is applied on a piston of area of cross section 2 cm 2 to obtain a force 150 N on the piston of area of cross section 12 cm 2 in a hydraulic machine ?
Assertion (A) : A brick exerts maximum pressure on ground when it is placed with its longest side vertical.
Reason (R) : Larger the area on which a given thrust acts, lesser is the pressure exerted by it.
- both A and R are true and R is the correct explanation of A
- both A and R are true and R is not the correct explanation of A
- assertion is false but reason is true
- assertion is true but reason is false
Assertion (A) : The walls of a dam are made thicker at the bottom.
Reason (R) : Pressure is the same in all directions about a point inside the liquid.
- both A and R are true and R is the correct explanation of A
- both A and R are true and R is not the correct explanation of A
- assertion is false but reason is true
- assertion is true but reason is false
A hydraulic jack is used in a car workshop to lift a car. The jack consists of two connected pistons A(area = 5 cm2) and B(area = 250 cm2), filled completely with an incompressible hydraulic fluid (such as hydraulic oil). The fluid transmits pressure uniformly throughout the system. A force of 120 N is applied vertically downward on piston A.
Assuming the system to be ideal, answer the following questions:
(a) Calculate the pressure produced in the liquid by piston A.
(b) Determine the force exerted on piston B. Name the law used.
(c) Does this hydraulic jack provide a gain in force or a gain in distance? Justify your answer.
(d) If piston B rises by a height of 2 cm, calculate the distance moved by piston A.
(e) What would happen if a small air bubble enters the liquid of the hydraulic jack?