Class 7 Science Chapter 10 Question Answers - Electric Current and Its Effects

Short Types Questions

An electric circuit diagram is a graphical representation of an electric circuit, showing the components of the circuit and their connections.

Q.2. What is the heating effect of electric current?

The heating effect of electric current is the production of heat energy in a conductor when an electric current flows through it.

Q.3. What is an electric fuse?

An electric fuse is a safety device that protects an electric circuit from damage by melting and breaking the circuit when the current exceeds a certain level.

Q.4. What is the magnetic effect of electric current?

The magnetic effect of electric current is the production of a magnetic field around a conductor when an electric current flows through it.

Q.5. What is an electric bell?

An electric bell is a device that uses an electromagnet to produce a ringing sound when an electric current flows through it. 

Long Types Questions

An electric circuit diagram is a graphical representation of an electric circuit. It shows the various components of the circuit and their connections with each other. The diagram helps in understanding how electricity flows through the circuit. It also helps in identifying the various components involved and their functions.
The flow of current in a circuit can be understood by looking at the diagram. The flow of current is always from the positive terminal to the negative terminal. The diagram shows the direction of current flow and the path it takes through the circuit. It also shows the voltage across each component and the resistance of each component.
In summary, an electric circuit diagram is a useful tool for understanding the flow of current in a circuit. It helps in identifying the various components involved and their functions. It also helps in troubleshooting any problems that may arise in the circuit.

Q.2. What is the heating effect of electric current? Explain with an example of an appliance that uses this effect.

The heating effect of electric current is the ability of electric current to produce heat energy. When an electric current flows through a conductor, the resistance of the conductor causes it to heat up. The amount of heat produced depends on the amount of current flowing through the conductor and the resistance of the conductor.
An example of an appliance that uses the heating effect of electric current is an electric iron. The iron has a heating element that is made of a conductor with high resistance. When current flows through the heating element, it heats up and transfers the heat to the metal plate of the iron. This heat is then used to iron clothes.
In summary, the heating effect of electric current is the ability of electric current to produce heat energy. An electric iron is an example of an appliance that uses this effect.

Q.3. What is an electric fuse? Explain its working and significance in an electric circuit. 

An electric fuse is a safety device that is used to protect an electric circuit from overloading or short-circuiting. It is a small wire or strip of metal that melts when the current flowing through it exceeds a certain limit. When the fuse melts, it breaks the circuit and stops the flow of current, thereby protecting the circuit and preventing any damage.
The working of an electric fuse is simple. When the current flowing through the circuit exceeds the rated value of the fuse, the temperature of the fuse wire increases. This increase in temperature causes the wire to melt, which breaks the circuit and stops the flow of current. The fuse can then be replaced with a new one.
The significance of an electric fuse in an electric circuit is that it protects the circuit from overloading or short-circuiting. It prevents any damage to the circuit and ensures the safety of the users.

Q.4. Explain the magnetic effect of electric current. Give an example of an application that uses this effect. 

The magnetic effect of electric current is the ability of electric current to produce a magnetic field around it. When an electric current flows through a conductor, it creates a circular magnetic field around the conductor. The strength of the magnetic field depends on the amount of current flowing through the conductor.
An example of an application that uses the magnetic effect of electric current is an electric motor. An electric motor consists of a coil of wire that is placed between two magnets. When current flows through the coil, it produces a magnetic field that interacts with the magnetic field of the magnets. This interaction causes the coil to rotate, which in turn rotates the shaft of the motor.
In summary, the magnetic effect of electric current is the ability of electric current to produce a magnetic field around it. An electric motor is an example of an application that uses this effect.

Q.5. Explain the working of an electric bell. What are the components involved in its operation?

An electric bell is a device that uses the magnetic effect of electric current to produce sound. It consists of an electromagnet, a striker, a spring, and a contact. When the circuit is closed, the current flows through the coil of the electromagnet, which produces a magnetic field. This magnetic field attracts the iron striker towards the electromagnet, causing it to strike the bell. The striker is attached to a spring, which pulls it back when the current is switched off. The contact is used to make and break the circuit.
The working of an electric bell can be summarized as follows:
1. The current flows through the coil of the electromagnet.
2. The electromagnet produces a magnetic field.
3. The magnetic field attracts the iron striker towards the electromagnet.
4. The striker strikes the bell, producing sound.
5. The contact is used to make and break the circuit.