Question 1 - Assertion Reasoning questions (MCQ) - Chapter 12 Class 10 - Electricity

Directions: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:

(a) Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).

(b) Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).

(c) Assertion (A) is true but reason (R) is false.

(d) Assertion (A) is false but reason (R) is true.

Assertion (A): A conductor has + 3.2 × 10 ^–19 C charge.

Reason (R): Conductor has gained 2 electrons.

Answer:

If a conductor has a positive charge then it means it has lost electrons.

Charge of one electron = 1.6 × 10 ^-19 C

Charge of conductor = 3.2 × 10 ^-19 C

Therefore, Number of electrons lost = Charge of conductor / Charge of one electron

            = 3.2 × 10 ^-19 / 1.6 × 10 ^-19 C

            = 2

So, the conductor has lost 2 electrons.

Thus,

• Assertion is true.
• Reasoning is false.

So, the correct answer is (c).