A hydraulic press has a ram of 20 cm diameter and a plunger of 5 cm d...
To find the force required at the plunger to lift a weight of 16 x 10^4 N, we can use Pascal's law, which states that the pressure in a fluid is transmitted equally in all directions.
Given:
Diameter of the ram = 20 cm
Radius of the ram = 10 cm
Area of the ram = πr^2 = π(10^2) = 100π cm^2
Diameter of the plunger = 5 cm
Radius of the plunger = 2.5 cm
Area of the plunger = πr^2 = π(2.5^2) = 6.25π cm^2
Weight to be lifted = 16 x 10^4 N
Using Pascal's law, we can say that the pressure at the ram is equal to the pressure at the plunger. Therefore, the force at the ram is equal to the force at the plunger.
Let F_r be the force at the ram, and F_p be the force at the plunger.
Given that the weight to be lifted is 16 x 10^4 N, which is equal to the force at the plunger (F_p).
Using the formula for pressure (P = F/A), we can calculate the pressure at the ram (P_r) and the pressure at the plunger (P_p).
Pressure at the ram:
P_r = F_r / A_r
P_r = F_r / (100π)
Pressure at the plunger:
P_p = F_p / A_p
P_p = F_p / (6.25π)
Since the pressure at the ram (P_r) is equal to the pressure at the plunger (P_p), we can equate the two equations:
F_r / (100π) = F_p / (6.25π)
Canceling out the common factor of π, we get:
F_r / 100 = F_p / 6.25
Cross multiplying, we get:
F_r = (F_p * 100) / 6.25
Substituting the value of F_p (16 x 10^4 N), we get:
F_r = (16 x 10^4 * 100) / 6.25
F_r = 256 x 10^4 / 6.25
F_r = 40 x 10^4 N
Therefore, the force required at the plunger to lift a weight of 16 x 10^4 N is 40 x 10^4 N, which is equivalent to 4 x 10^4 N. Hence, the correct answer is option D.
To make sure you are not studying endlessly, EduRev has designed Railways study material, with Structured Courses, Videos, & Test Series. Plus get personalized analysis, doubt solving and improvement plans to achieve a great score in Railways.