1. The energy conversion in a wind turbine is from:
(A) Electrical to Mechanical
(B) Mechanical to Electrical
(C) Kinetic to Electrical
(D) Potential to Thermal
2. The power available in the wind is proportional to:
(A) Wind speed
(B) Square of wind speed
(C) Cube of wind speed
(D) Fourth power of wind speed
3. The part of a wind turbine that converts rotational energy into electricity is called:
(A) Rotor
(B) Gearbox
(C) Generator
(D) Tower
4. The component that connects the rotor to the generator is:
(A) Shaft
(B) Hub
(C) Gearbox
(D) Bearing
5. The efficiency limit for wind energy conversion, known as Betz limit, is:
(A) 16.7%
(B) 33.3%
(C) 59.3%
(D) 75%
6. The main type of generator used in wind energy systems is:
(A) DC Generator
(B) Synchronous Generator
(C) Induction Generator
(D) Stepper Motor
7. The cut-in speed of a wind turbine is:
(A) Minimum speed for rated power
(B) Speed at which turbine starts generating power
(C) Speed at which turbine stops
(D) Maximum safe wind speed
8. The cut-out speed of a wind turbine is:
(A) When power output is maximum
(B) When the turbine stops to prevent damage
(C) When wind speed is zero
(D) When generator efficiency is lowest
9. The height of the wind turbine tower affects:
(A) Rotor speed
(B) Wind speed availability
(C) Power losses
(D) Generator type
10. The power coefficient (Cp) of a wind turbine is the ratio of:
(A) Output power to wind power
(B) Mechanical power to electrical power
(C) Kinetic energy to mechanical energy
(D) Generator efficiency
11. The wind energy conversion system (WECS) with a horizontal axis has its axis of rotation:
(A) Vertical
(B) Inclined
(C) Horizontal
(D) Circular
12. Which type of wind turbine operates irrespective of wind direction?
(A) Horizontal axis turbine
(B) Vertical axis turbine
(C) Offshore turbine
(D) Yaw-controlled turbine
13. The main advantage of vertical axis wind turbines is:
(A) High efficiency
(B) Independent of wind direction
(C) Low noise
(D) Easy control
14. The main disadvantage of vertical axis wind turbines is:
(A) Complex construction
(B) High maintenance
(C) Low efficiency
(D) Large tower height
15. The tip-speed ratio (TSR) is defined as:
(A) Blade tip speed / Wind speed
(B) Wind speed / Blade tip speed
(C) Rotor speed / Gearbox ratio
(D) Power / Area
16. In a wind turbine, the pitch control mechanism is used to:
(A) Increase wind speed
(B) Control rotor speed and power
(C) Measure wind direction
(D) Support turbine weight
17. The yaw control system in a wind turbine:
(A) Adjusts blade angle
(B) Aligns turbine with wind direction
(C) Stops the turbine
(D) Measures power output
18. The gearbox in a wind turbine is used to:
(A) Increase torque
(B) Reduce noise
(C) Increase rotational speed for the generator
(D) Control yaw
19. The swept area of a wind turbine is proportional to:
(A) Rotor diameter
(B) Rotor radius squared
(C) Rotor speed
(D) Wind pressure
20. The rated wind speed of a wind turbine is the speed at which:
(A) Power output is zero
(B) Power output is maximum
(C) Turbine shuts down
(D) Power factor is unity
21. The main environmental advantage of wind energy is that it:
(A) Produces noise
(B) Emits greenhouse gases
(C) Is renewable and clean
(D) Needs fossil fuels
22. The mechanical energy from the turbine is converted to electrical energy using a:
(A) Motor
(B) Alternator
(C) Generator
(D) Transformer
23. The wind power density is measured in:
(A) W/m²
(B) kWh
(C) J/m³
(D) Nm
24. The output of a wind turbine depends on:
(A) Wind speed
(B) Air density
(C) Rotor area
(D) All of the above
25. A typical modern wind turbine has how many blades?
(A) 1
(B) 2
(C) 3
(D) 4
26. Offshore wind turbines generally have:
(A) Smaller capacity
(B) Larger capacity
(C) Fixed blades
(D) Lower efficiency
27. The drag-type wind turbine example is:
(A) Savonius turbine
(B) Darrieus turbine
(C) HAWT
(D) Pelton wheel
28. The lift-type vertical axis turbine is known as:
(A) Savonius turbine
(B) Darrieus turbine
(C) Kaplan turbine
(D) Francis turbine
29. The main disadvantage of wind energy is:
(A) Renewable nature
(B) Intermittent power generation
(C) No pollution
(D) Low maintenance
30. The ultimate source of wind energy is:
(A) The Moon
(B) The Sun
(C) The Ocean
(D) The Earth’s Core