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
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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
What does servo mean in servo valve system?
A. it cannot receive a feedback but the desired output can be obtained
B. it cannot receive a feedback and the desired output cannot be obtained
C. it can receive a feedback and the desired output can be obtained
D. none of the above
In conventional valves, which component is used to move the spool?
A. torque motor
B. mechanical servo valve
C. solenoid
D. all the above
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