In the hydraulic system, the valve used to regulate the flow of liquid into the actuator is ( )
A. relief valve
B. check valve
C. speed regulating valve
D. directinonal control valve
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The pressure loss at the pressure reducing valve in the hydraulic system belongs to
A. pressure loss along the way
B. local pressure loss
C. both
D. neither
How is strong magnetic field in a solenoid achieved ?
A. strong magnetic field in a solenoid is achieved, if coil acts as conductor
B. coil is surrounded by a iron frame
C. iron core is placed at the centre of the coil
D. all the above
What is the DC range of of solenoids in pneumatic systems?
A. 12 V and 24 V
B. 110 V and 220 V
C. both a and b
D. none of the above
In which systems, spool of the servo valve is operated by a torque motor?
A. hydro-mechanical servo systems
B. electro-hydraulic servo systems
C. conventional servo valve
D. all the above
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