Class 7 Science Chapter 3 NCERT Solutions: Electricity, Circuits and Their Components

1. Multiple choice questions.

1. Which of the following is a good conductor of electricity?

• (a) Paper
• (b) Glass
• (c) Copper
• (d) Rubber

Answer: (c) Copper

2. Which symbol is used for the electric cell in a circuit diagram?

• (a)
• (b)
• (c)
• (d)

Answer: (b)

2. Answer the following questions in about 30 words.

1. What is an electric circuit?

Answer: An electric circuit is a closed path through which electric current flows. It consists of components such as a cell, switch, and bulb connected by wires, allowing current to complete its loop and operate devices like lamps.

2. What are conductors and insulators? Give examples.

Answer: Conductors are materials that allow electric current to pass through them easily, such as copper and aluminium. Insulators do not allow current to pass through, like rubber, glass, and plastic.

3. What is the direction of flow of electric current in a circuit?

Answer: The direction of flow of electric current in a circuit is from the positive terminal to the negative terminal of the electric cell.

4. What are circuit symbols? Why are they used?

Answer: Circuit symbols are special signs used to represent electrical components in a circuit diagram. They make drawing and understanding circuits easier and universally recognizable.

3. Answer the following questions in about 150 words.

1. Explain the uses of electricity in daily life as discussed in the chapter.

Answer: Electricity is widely used in our daily lives for various purposes. It provides entertainment by powering televisions and computers, supports communication through telephones and mobiles, and is essential for lighting homes, streets, and workplaces. In the kitchen, electrical appliances like ovens and mixers help with cooking. Transport systems, such as electric trains and vehicles, rely heavily on electricity. Additionally, it is used for heating and cooling in the form of geysers, electric heaters, fans, air conditioners, and refrigerators. Thus, electricity has made life more convenient, comfortable, and efficient by supporting numerous activities under different categories like Entertainment, Communication, Lighting, Cooking, Transportation, and Heating and Cooling.

2. Describe the process of constructing and testing a simple electric circuit at home.

Answer: To construct a simple electric circuit at home, take an electric cell, a bulb, wires, and a switch. Connect one end of the wire to the positive terminal of the cell and the other end to one terminal of the bulb. Use another wire to connect the other terminal of the bulb to the negative terminal of the cell, completing the circuit. Insert a switch along one wire if you want to control the bulb. When the switch is closed (ON), the circuit is complete, and the bulb glows. When open (OFF), the current stops, and the bulb does not glow. This setup helps students understand the flow of electricity and the function of various circuit components.

4. Match the following.

Understanding Electricity, Circuits, and Their Components

Mastering the basics of electricity and circuit components is crucial for scoring well in Class 7 Science. This chapter makes concepts like cells, batteries, conductors, and insulators easy to grasp for every learner.

Comprehending how electric circuits work through practical activities helps students apply knowledge beyond the textbook. Recognizing the flow direction of current and understanding circuit symbols will give you an edge in exams.

Practice is key—revise exercise-based questions and perform hands-on circuit activities to build confidence. These steps will boost your clarity on the topic and enhance your exam performance in Science Class 7.