Exam Practice Questions And Correct

Hydro Power Plant Operator License Exam Practice Questions And Correct Answers (Verified Answers) Plus Rationales 2026 Q&A | Instant Download Pdf

• What is the main function of a hydroelectric power plant?
• Store water for irrigation
• Provide drinking water
• Generate electricity
• Control floods

Rationale: The primary purpose of a hydroelectric plant is to convert the

potential and kinetic energy of water into electrical energy.

• Which component of a hydroelectric plant converts mechanical energy

into electrical energy?

• Dam 1 / 4

• Penstock
• Generator
• Surge tank

Rationale: The generator transforms the rotational mechanical energy of

the turbine into electricity.

3. The vertical drop of water in a hydroelectric plant is called:

• Flow rate
• Head
• Capacity
• Discharge

Rationale: Head refers to the height difference between the water source

and the turbine, determining potential energy.

• What type of turbine is most suitable for high-head hydroelectric

plants?

• Kaplan turbine
• Propeller turbine
• Pelton wheel
• Francis turbine

Rationale: Pelton turbines are impulse-type turbines ideal for high-head,

low-flow conditions.

• The part of the turbine that interacts directly with water to produce

motion is called:

• Shaft 2 / 4

• Runner
• Stator
• Nozzle

Rationale: The runner is the rotating part of the turbine that converts

water energy into rotational mechanical energy.

6. A surge tank is used in hydroelectric plants to:

• Store water for peak demand
• Reduce water hammer and pressure fluctuations
• Increase generator output
• Maintain water temperature

Rationale: Surge tanks absorb sudden changes in water flow, preventing

water hammer in penstocks.

• Which of the following is a measure of the amount of water flowing

through the turbine?

• Head
• Discharge (flow rate)
• Capacity factor
• Efficiency

Rationale: Discharge refers to the volume of water passing through the

turbine per unit time.

8. The efficiency of a hydroelectric turbine is defined as:

• Power input divided by water volume
• Mechanical power output divided by water power input 3 / 4

• Water flow divided by head
• Generator voltage divided by current

Rationale: Turbine efficiency measures how effectively it converts water

energy into mechanical energy.

• The device that converts the turbine’s rotational energy into alternating

current is the:

• Exciter
• Transformer
• Generator
• Inverter

Rationale: Generators produce AC electricity by electromagnetic induction

using the turbine’s motion.

• What is the primary purpose of the draft tube in a reaction turbine?
• Increase water velocity
• Reduce turbine speed
• Recover kinetic energy and reduce exit velocity
• Direct water to the penstock

Rationale: Draft tubes slow down water exiting the turbine, converting

kinetic energy into useful pressure and improving efficiency.

• Which of the following types of dams is constructed using large

quantities of concrete?

• Embankment dam
• Gravity dam
• / 4