QUESTIONS (within 11.1)
Q1. What does an electric circuit mean?
Answer:
An electric circuit is a continuous and closed path of an electric current. It consists of a cell (or battery), a plug key, electrical components, and connecting wires. The circuit must be complete for current to flow.
Q2. Define the unit of current.
Answer:
The unit of current is the ampere (A). One ampere is constituted by the flow of one coulomb of charge per second, that is, 1 A = 1 C/1 s.
Q3. Calculate the number of electrons constituting one coulomb of charge.
Answer:
We know that the charge of one electron is 1.6 × 10?¹? C. Number of electrons = Total charge / Charge of one electron = 1 C / (1.6 × 10?¹? C) = 6.25 × 10¹? electrons. So, approximately 6 × 10¹? electrons constitute one coulomb of charge.
QUESTIONS (within 11.2)
Q1. Name a device that helps to maintain a potential difference across a conductor.
Answer:
A cell or a battery helps to maintain a potential difference across a conductor. The chemical action within a cell generates the potential difference across its terminals.
Q2. What is meant by saying that the potential difference between two points is 1 V?
Answer:
It means that 1 joule of work is done to move a charge of 1 coulomb from one point to the other.
Q3. How much energy is given to each coulomb of charge passing through a 6 V battery?
Answer:
Given, Potential difference V = 6 V, Charge Q = 1 C. Energy (Work done) W = V × Q = 6 V × 1 C = 6 J. So, 6 joules of energy is given to each coulomb of charge.