Class 10 Science Chapter 11 Question Answers - Electricity

Short Answer Questions

Q1: What is electricity?
Ans: Electricity is a form of energy that powers our appliances and activities.

Q2: Explain the structure of an electric cell.
Ans: An electric cell has a positive (+) metal cap and a negative (—) metal disc at the bottom. It is filled with chemicals that produce electricity.

Q3: How does an electric bulb produce light and heat?
Ans: When electricity flows through the tungsten filament in the bulb, it becomes hot and produces light and heat.

Q4: Why does a bulb fuse, and what happens when it fuses?
Ans: A bulb fuses when its filament breaks. When fused, the bulb cannot produce light and needs to be replaced.

Q5: What are the benefits of using Light Emitting Diodes (LEDs)?
Ans: LEDs last longer (6 to 11 years), consume less electricity, produce less heat, and are almost unbreakable compared to ordinary bulbs.

Long Answer Questions

Q1: Describe the structure of an electric cell and how it produces electricity.
Ans:  electric cell has a positive metal cap and a negative metal disc filled with chemicals. When these chemicals react, they produce electricity, converting chemical energy into electrical energy.

Q2: Explain the process of generating electricity in a hydroelectric power plant.
Ans: A hydroelectric power plant uses the force of flowing water to turn turbines, which generate electricity. This method is non-polluting and involves constructing dams on rivers.

Q3: Discuss the importance of a resistor in an electric circuit with an LED.
Ans: A resistor controls the flow of electric current in a circuit. In the case of an LED circuit, it prevents excess current, protecting the LED from damage. Without a resistor, the LED may fuse instantly.

Q4: What are conductors and insulators? Provide examples of each.
Ans: Conductors allow electricity to pass through (e.g., copper), while insulators do not (e.g., plastics, fiberglass). Copper is commonly used in good-quality electric wires.

Q5: Describe the role of a switch in an electric circuit and give examples.
Ans: A switch completes or breaks an electric circuit. In the 'ON' position, the circuit is complete, and the appliance works; in the 'OFF' position, the circuit breaks. Switches are crucial for controlling the flow and direction of electric current.