250+ TOP MCQs on Electro-Pneumatics and Answers

Mechatronics Multiple Choice Questions on “Electro-Pneumatics”.

1. Which is an electro-pneumatic device?
a) Seven Segment display
b) BO Motor
c) Hydraulic cylinder
d) Lithium battery
Answer: c
Clarification: Hydraulic cylinder is an electro-pneumatic device. Pneumatics refers to the system or devices that is being controlled or operated by the means of air pressure. Hydraulic cylinders often use inert fluids.

2. Which actuator does not need any external power source?
a) 3 phase motor
b) Solenoid valve
c) Wax Motor
d) BO motor
Answer: c
Clarification: Wax Motor is a linear actuator does not need any external power source. It converts thermal energy to mechanical energy. It works on the principle of expansion of wax when it is converted to liquid form.

3. How many directions are there, for a fluid to flow in check valves?
a) 1
b) 2
c) 3
d) 4
Answer: a
Clarification: There is only 1 direction for a fluid to flow in check valves. The movement of flow of compressed gas or any fluid is unidirectional. The Valve automatically opens when the fluid enters the inlet with some specific pressure.

4. How many directions are there, for a fluid to flow in shuttle valves?
a) 1
b) 2
c) 3
d) 4
Answer: b
Clarification: There are only 2 directions for a fluid to flow in shuttle valves. It allows inlet from 2 different directions. A dynamic shuttle is used to switch the flow from the inputs. Fluid flows from the inlet which is experiencing higher pressure.

5. The OPEN and CLOSE time of an electro pneumatic valve can be controlled using PLC control system.
a) True
b) False
Answer: a
Clarification: The ON and OFF time of a buzzer can be controlled using PLC control system. PLC stands for programmable logic controller. It is a digital computer that can control electromechanical machines. The ON and OFF time of a buzzer can be easily controlled through it.

6. Thermal actuators need electric current for operation.
a) True
b) False
Answer: b
Clarification: Thermal actuators do not need electric current for operation. It is made up of a cylinder, piston and a thermal sensitive material. When this actuator comes in contact with heat the thermal sensitive material expands and pushes the piston out.

7. What is the full form DCV in terms of pneumatic control systems?
a) Delicate Control Valve
b) Distance Control Value
c) Directional Control Valve
d) Diameter Control Valve
Answer: c
Clarification: Directional Control Valve is the full form DCV in terms of pneumatic control systems. These directional control valves are used to control the direction of flow of any compressed gas or fluid.

8. Which valve should be used if there is a need of fluid to flow in 4 directions?
a) Spool valve
b) Shuttle Valve
c) Check valve
d) Rubber valve
Answer: a
Clarification: Spool valve should be used if there is a need of fluid to flow in 4 directions. It can also be used for bidirectional and tri-directional flow of fluid. Shuttle Valve allows only two inlets of fluid and Check valve only allows unidirectional flow of fluids.

9. Which valve works on electricity and not on pressure difference?
a) Rubber valve
b) Pilot Valve
c) Check valve
d) Solenoid valve
Answer: d
Clarification: Solenoid valve works on electricity and not on pressure difference. When the electricity passes through the solenoid, it acts as a switch. By manipulating the electrical signal it can open and close the valve as per the requirement.

10. Which is an example of pressure regulator?
a) R100UD
b) CMCP793V-500
c) SLB700A/06VA
d) FN2060A-6-06
Answer: a
Clarification: R100UD is an example of pressure regulator. It is a single stage pressure regulator. It is made up of cast aluminum. It can regulate pressure of oxygen, nitrogen, propane, compressed air and other natural gasses.

11. Who invented check valve?
a) Norbert wiener
b) Robert Wiener
c) Charles young
d) Frank P. Cotter
Answer: d
Clarification: Frank P. Cotter invented check valve. He invented the first check valve in the year 1907. The valve was easy to install, repair and maintain. Further many types of check valve were invented such as “Tesla valve” invented by Nicola Tesla.

12. Solenoid valves cannot be used for controlling the valve of a liquid flowing through a channel.
a) True
b) False
Answer: b
Clarification: Solenoid valves can be used for controlling the valve of a liquid flowing through a channel. It can be used for controlling the valve of any fluid flowing through a channel. When current flows through the solenoid, it acts as a switch.

13. Wax motor does not require external electrical power source.
a) True
b) False
Answer: a
Clarification: Wax motor does not require external electrical power source. It performs linear actuation by exploiting the phase change behavior of different waxes. When the waxes melt due to heat, it can expand up to 20% of its volume.

14. What type of motion can be achieved using thermal actuator?
a) Rectilinear
b) Spiral
c) Circular
d) Parabolic
Answer: a
Clarification: Rectilinear motion can be achieved using thermal actuator. It is a non electric type linear actuating setup which is made up of a cylinder, piston and a thermal sensitive material. When this actuator comes in contact with heat the thermal sensitive material expands and pushes the piston out.

15. Which is an example of push pull solenoid electromagnet?
a) R100UD
b) CMCP793V-500
c) SLB700A/06VA
d) JF-0630B
Answer: d
Clarification: JF-0630B is an example of push pull solenoid electromagnet. It works on 12 volt DC supply with operating current of 1 ampere. It can provide holding force up to 6 Newton. It is used when there is a requirement of a linear actuation. Example: Door locks.