Study Materials

# NCERT Solutions for Class 10th Science

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## Chapter 12. Electricity

Chapter-12. Electricity

Q1: What is an electric circuit?

Ans: A continuous and closed path of an electric current is called an electric circuit.

Q2: Name the instrument which measures electric current in a circuit.

Ans: Ammeter.

Q3: In which order, an ammeter is connected in a circuit?

Ans: In series.

Q4: In which direction does the electric current flow in a circuit?

Ans: the electric current flows in the circuit from positive terminal of the cell to negative terminal of the cell.

Q5: Name the device which produces potential difference in a wire?

Ans: Cell or battery.

Q6: What is potential difference?

Ans: The electrons move only if there is a difference of electric pressure in a conducting metallic wire. This difference of electric pressure is called potential difference.

Q7: Two bulbs of 100 W and 25 W are connected in series to 200 V-AC mains. Which bulb glows brightly? Explain your observation.

Q8: Why does the element of a room heater become red hot but the lead wires remain cold?

Ans:  The element of a room heater has high resistance. According to jule’s law of heating , increasing in resistance cause increasing in heat. While the device wire has not so highly resistance.

Q9: Calculate the number of electrons constituting one coulomb of charge.

Ans: 6 x1018 electrons.

Q10: State the Ohm’s Law.

Ans: The electric current flowing through a metallic wire is directly proportional to the potential difference V, across its ends provided its temperature remains the same. This is called Ohm’s law.

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