Possible reasons are as follows: • The bulb may be fused or defective. • Cells are not connected properly. • There may be loose connections. • The switch is not functioning well. • The cells are dried up i.e. the power of the cell has been exhausted. https://www.tiwariacademy.com/ncert-solutions/claRead more
Possible reasons are as follows:
• The bulb may be fused or defective.
• Cells are not connected properly.
• There may be loose connections.
• The switch is not functioning well.
• The cells are dried up i.e. the power of the cell has been exhausted.
Fuse is a device that is a safeguard to all of our electrical appliances. They are made up of special material which melt quickly and break when a large electric currents passed through it. If the electrician does not use proper fuse wire, instead he uses any ordinary electric wire as fuse, it increRead more
Fuse is a device that is a safeguard to all of our electrical appliances. They are made up of special material which melt quickly and break when a large electric currents passed through it.
If the electrician does not use proper fuse wire, instead he uses any ordinary electric wire as fuse, it increases the risk of overheating of wires due to flow of excessive current. It may lead to short circuit in electric equipment and these appliances may catch fire. It is advised to use standard fuse wire or MCBs to prevent electrical accidents.
An electromagnet is just like as a bar magnet and it can attract iron pieces only. Plastic does not have any magnetic property, so electromagnet cannot be used to separate plastic bags from garbage heap. https://www.tiwariacademy.com/ncert-solutions/class-7/science/chapter-14/
An electromagnet is just like as a bar magnet and it can attract iron pieces only. Plastic does not have any magnetic property, so electromagnet cannot be used to separate plastic bags from garbage heap.
The safety device based on the heating effect of electric current is called a fuse. https://www.tiwariacademy.com/ncert-solutions/class-7/science/chapter-14/
The safety device based on the heating effect of electric current is called a fuse.
Zubeda made an electric circuit using a cell holder, a switch and a bulb. When she put the switch in the ‘ON’ position, the bulb did not glow. Help Zubeda in identifying the possible defects in the circuit.
Possible reasons are as follows: • The bulb may be fused or defective. • Cells are not connected properly. • There may be loose connections. • The switch is not functioning well. • The cells are dried up i.e. the power of the cell has been exhausted. https://www.tiwariacademy.com/ncert-solutions/claRead more
Possible reasons are as follows:
• The bulb may be fused or defective.
• Cells are not connected properly.
• There may be loose connections.
• The switch is not functioning well.
• The cells are dried up i.e. the power of the cell has been exhausted.
https://www.tiwariacademy.com/ncert-solutions/class-7/science/chapter-14/
See lessAn electrician is carrying out some repairs in your house. He wants to replace a fuse by a piece of wire. Would you agree? Give reasons for your response.
Fuse is a device that is a safeguard to all of our electrical appliances. They are made up of special material which melt quickly and break when a large electric currents passed through it. If the electrician does not use proper fuse wire, instead he uses any ordinary electric wire as fuse, it increRead more
Fuse is a device that is a safeguard to all of our electrical appliances. They are made up of special material which melt quickly and break when a large electric currents passed through it.
If the electrician does not use proper fuse wire, instead he uses any ordinary electric wire as fuse, it increases the risk of overheating of wires due to flow of excessive current. It may lead to short circuit in electric equipment and these appliances may catch fire. It is advised to use standard fuse wire or MCBs to prevent electrical accidents.
https://www.tiwariacademy.com/ncert-solutions/class-7/science/chapter-14/
See lessDo you think an electromagnet can be used for separating plastic bags from a garbage heap? Explain.
An electromagnet is just like as a bar magnet and it can attract iron pieces only. Plastic does not have any magnetic property, so electromagnet cannot be used to separate plastic bags from garbage heap. https://www.tiwariacademy.com/ncert-solutions/class-7/science/chapter-14/
An electromagnet is just like as a bar magnet and it can attract iron pieces only. Plastic does not have any magnetic property, so electromagnet cannot be used to separate plastic bags from garbage heap.
https://www.tiwariacademy.com/ncert-solutions/class-7/science/chapter-14/
See lessFill in the blanks: The safety device based on the heating effect of electric current is called a ____________.
The safety device based on the heating effect of electric current is called a fuse. https://www.tiwariacademy.com/ncert-solutions/class-7/science/chapter-14/
The safety device based on the heating effect of electric current is called a fuse.
https://www.tiwariacademy.com/ncert-solutions/class-7/science/chapter-14/
See lessFill in the blanks: When current is switched ‘on’ in a room heater, it ____________.
When current is switched ‘on’ in a room heater, it becomes hot. https://www.tiwariacademy.com/ncert-solutions/class-7/science/chapter-14/
When current is switched ‘on’ in a room heater, it becomes hot.
https://www.tiwariacademy.com/ncert-solutions/class-7/science/chapter-14/
See less