What are CFLs ? Why are CFLs preferred over electric bulbs ?

(a) Why does a glowing electric bulb become warm?
(b) Mention any two effects of electric current.
(c) Why does a glowing CFL not become warm?

(i) What is the heating effect of electric current?
(ii) Name two appliances that make use of heating effect of electric current.
(iii) Name the safety device based on the heating effect of electric current.

One day, Pinki was ironing the clothes in her room. After half an iron of ironing, the light went off and Pinki went outside to the lobby of her house to check it there was any problem in the household circuit. At the same time, she listened the voice of her 4 years old daughter from the same room where she was ironing the clothes. Her daughter was about to touch the hot electric iron but at the same moment, Pinki entered in the room and pushed her daughter back from that place.
(a) On which effect of electric current, does the electric iron works?
(b) Mention the values showed by Pinki here.

State one measure to avoid overloading in an electrical circuit. Also mention the name given to a situation in which the live and the neutral wires accidently come in contact. Describe the role of a safety device in this situation.

Paheli took a wire of length 10 cm. Boojho took a wire of 5 cm of the same material and thickness both of them connected with wires as shown in the circuit given in figure. The current flowing in both the circuits is the same.
(a) Will the heat produced in both the cases be equal? Explain.
(b) Will the heat produced be the same, if the wires taken by them are of equal lengths but of different thickness? Explain.

Last Sunday, Pulpit was playing videotape in his room. While playing, the electricity of his house went off due to which he could not able to see anything around him. Then anyhow, he managed to get his mobile in his hand and with the help of its light, he went outside of his room to check if there was any problem in the electric circuit board of his house.
At the same time, his father suggested him to maintain the distance from the circuit board and decided to call some electrician to check the problem.
(a) Explain, what happens when live wire and neutral wire touches each other directly?
(b) State the values here showed by Pulkit's father.

What do you understand by electric circuit? Write its components

What is an electromagnet? Write its uses.

Explain the working of electric bell with diagram