Q1. Fill in the blanks.
do not allow current to pass through them.
Air is an insulator.
Our body is a good conductor of
The metal cap is the positive
terminal of the electric cell.
Impure water can also conduct electricity. True
An electric cell produces electricity from
the chemicals stored inside it. True
The metal disc is the positive terminal. False
Brass is a conductor. True
Insulators allow current to pass through
Q3. Which device is used to open or close an electric circuit?
Q4. Who invented the first electric bulb?
Thomas Alva Edison invented the first electric bulb.
Q5. Who invented the first electric cell?
Alessandro Volta invented the first electric cell.
Q6. Which is the +ve terminal of a cell?
The metal cap is the positive terminal of the electric cell.
Q7. Which is the –ve terminal of a cell?
The metal disc is the negative terminal of the electric cell.
Q8. Who invented dry cell?
French chemist Georges Leclanche invented dry cell.
Q9. Define an electric switch.
A switch is a simple device that either breaks the circuit or completes it.
Q10. Where does the torch get electricity from?
Electricity to the bulb in a torch is provided by the electric cell.
Q11. Where does electricity come from?
A power station provides us with electricity.
Q12. How does an electric cell produce electricity?
An electric cell converts chemical energy into electricity.
Q13. Name the type of circuit in which switch is in ‘OFF’
Q14. Can distilled water conduct electricity?
No, distilled or pure water does not conduct electricity.
Q15. Name the type of circuit in which switch is in ‘ON’
Closed circuit or complete circuit
Q16. Can tap water or rain water conduct electricity?
Yes, tap water or rain water can conduct electricity.
Q17. What is a thin wire fixed in the middle of the glass bulb
A thin wire fixed in the middle of the glass bulb is called a filament.
Q18. What is a filament in a light bulb?
The thin wire that gives off light is called the filament of the bulb.
Q19. Write two examples of conductor and insulators.
Conductor – Copper and Aluminium
Insulators – Plastic and Rubber
Q20. What is heating effect of current?
Heating caused due to conversion of electrical energy into heat energy is
called heating effect of current.
Q21. Will the bulb glow in an open circuit? Why or why not?
Bulb does not glow in an open circuit because the bulb glows only when current
flows through the circuit.
Q22. What is an electric bulb?
An electric bulb (or a light bulb) is a device that converts electrical energy
into light energy.
Q23. What are the two terminals called in an electric cell?
All electric cells have two terminals; a positive terminal and a negative