Q1. A hydraulic press has a ram of 15 cm diameter and plunger of 1.5 cm. It is required to lift a mass of 1000kg. The force required on plunger is nearly equal to

(a) 100N

(b) 1000N

(d) 10N

Ans (a)

By pascal law:

F1/A1 = F2/A2

F1/3.14(1.5)^2/4 = 1000×10/3.14(15)^2/4

F1 = 100N...................................................................................................(Ans)

*3.14 is value of piπ

*F2= 1000×10= m×g= mass×acceleration due to gravity(9.8)

*A1= 3.14(1.5)^2/4 =πd²/4 = area of circle

*A2= 3.14(15)^2/4 = πd²/4

*15 cm diameter value of circle at point2

*1.5 cm diameter value of circle at point1

Comments

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