i. Insulators do not allow current to pass through them.
ii. Air is an insulator.
iii. Our body is a good conductor of electricity.
iv. The metal cap is the positive terminal of the electric cell.
i. Impure water can also conduct electricity. True
ii. An electric cell produces electricity from the chemicals stored inside it. True
iii. The metal disc is the positive terminal. False
iv. Brass is a conductor. True
v. Insulators allow current to pass through them. False
Ans. Electric switch
Ans. Thomas Alva Edison invented the first electric bulb.
Ans. Alessandro Volta invented the first electric cell.
Ans. The metal cap is the positive terminal of the electric cell.
Ans. The metal disc is the negative terminal of the electric cell.
Ans. French chemist Georges Leclanche invented dry cell.
Ans. A switch is a simple device that either breaks the circuit or completes it.
Ans. Electricity to the bulb in a torch is provided by the electric cell.
Ans. A power station provides us with electricity.
Ans. An electric cell converts chemical energy into electricity.
Ans. Open circuit
Ans. No, distilled or pure water does not conduct electricity.
Ans. Closed circuit or complete circuit
Ans. Yes, tap water or rain water can conduct electricity.
Ans. A thin wire fixed in the middle of the glass bulb is called a filament.
Ans. The thin wire that gives off light is called the filament of the bulb.
Ans. Conductor – Copper and Aluminium
Insulators – Plastic and Rubber
Ans. Heating caused due to conversion of electrical energy into heat energy is called heating effect of current.
Ans. Bulb does not glow in an open circuit because the bulb glows only when current flows through the circuit.
Ans. An electric bulb (or a light bulb) is a device that converts electrical energy into light energy.
Ans. All electric cells have two terminals; a positive terminal and a negative terminal.
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