Question 21 markShort AnswerSection A

Write the energy conversion that takes place in a hydropower plant.

Our Environment
Food Chains and Webs

Official answer

In a hydropower plant, the potential energy of water stored at a height is converted into the kinetic energy of falling water, which is then converted into mechanical energy by rotating a turbine, and finally into electrical energy by a generator.

Answer keywords:Potential energyKinetic energyMechanical energyElectrical energyTurbineGenerator

Marking scheme

  1. 1.Identification of initial energy (Potential energy of stored water): 0.5 marks
  2. 2.Sequence of conversion to electrical energy (Potential →\rightarrow Kinetic →\rightarrow Mechanical →\rightarrow Electrical): 0.5 marks

Hint

Think about how water stored at a height has energy due to its position, which changes to motion as it falls, turns a turbine, and finally generates electricity.

Quick oral answer

In a hydropower plant, the potential energy of stored water is converted into the kinetic energy of falling water, which rotates a turbine to produce mechanical energy, and is finally converted into electrical energy by a generator.

Common mistakes

  1. 1.Stating that potential energy is directly converted to electrical energy without mentioning kinetic or mechanical energy.
  2. 2.Confusing the stored energy of water with chemical energy.

Analysis and explanation

The water stored in a high-altitude reservoir possesses potential energy due to its position. When this water is released, it flows down under gravity, converting its potential energy into kinetic energy. This fast-moving water strikes the blades of a water turbine, converting kinetic energy into mechanical energy (rotational motion). The turbine is coupled to an electric generator, which converts this mechanical energy into electrical energy.


Potential Energy of Stored Water→Kinetic Energy of Flowing Water→Mechanical Energy of Turbine→Electrical Energy\text{Potential Energy of Stored Water} \rightarrow \text{Kinetic Energy of Flowing Water} \rightarrow \text{Mechanical Energy of Turbine} \rightarrow \text{Electrical Energy}

Interesting facts

Hydropower is a renewable source of energy and currently accounts for a significant share of the world's electricity generation, dating back to the late 19th century.

Question details

Q2 of 27 questions

Board
CBSE
Class
Class 10
Subject
Science
Year
2018
Section
Section A
Marks
1
Type
Short Answer
Chapter
Our Environment
Topic
Food Chains and Webs
Bloom's level
Remembering
Syllabus topic
Energy flow in ecosystem and energy conversions

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Frequently asked questions

How many marks does this question carry in CBSE Class 10 Science 2018?

This question carries 1 mark in the CBSE Class 10 Science 2018 examination.

Which chapter does this question come from in Science?

This question is from the chapter "Our Environment" in the CBSE Class 10 Science syllabus.

What topic does this question cover in Science?

This question covers the topic "Food Chains and Webs" from CBSE Class 10 Science.

What type of question is this in the CBSE Class 10 Science 2018 paper?

This is a Short Answer question from Section A in the CBSE Class 10 Science 2018 paper.