Question 131 markMCQSection A

Two LED bulbs of 12W12W and 6W6W are connected in series. If the current through 12W12W bulb is 0.06A0.06A the current through 6W6W bulb will be :

Electricity
Electric Current and Circuit

Options

(a)0.04A
(b)0.06A
(c)0.08A
(d)0.12A

Official answer

Option (b) is correct.

Answer keywords:series connectioncurrent remains same0.06 A

Marking scheme

  1. 1.Identification of series connection property (current remains constant): 0.5 Mark
  2. 2.Stating the correct current value (0.06 A0.06\text{ A}): 0.5 Mark

Hint

Recall that in a series connection, the current flowing through each electrical component is the same.

Quick oral answer

In a series circuit, the current has only one path to flow, so the current through every component is identical. Therefore, both bulbs experience a current of 0.06 A0.06\text{ A}.

Common mistakes

  1. 1.Students often try to use the power formula (P=I2RP = I^2 R or P=VIP = VI) to calculate individual resistances and then recalculate current, which is unnecessary and can lead to calculation errors since the series current is already given.

Analysis and explanation

In a series circuit, there is only a single path for the flow of electric charge. Consequently, the electric current (II) remains identical through all components connected in series. Since the 12 W12\text{ W} LED bulb and the 6 W6\text{ W} LED bulb are connected in series, the current flowing through the 6 W6\text{ W} bulb must be exactly equal to the current flowing through the 12 W12\text{ W} bulb, which is 0.06 A0.06\text{ A}.


  • Why other options are incorrect:
  • Option (a) 0.04 A0.04\text{ A}, Option (c) 0.08 A0.08\text{ A}, and Option (d) 0.12 A0.12\text{ A} are incorrect because they assume that current divides or changes across components in a series circuit, which violates the law of conservation of charge in a single-loop circuit.

Interesting facts

Because current is constant in a series circuit, if one bulb in a series string fuses or is removed, the entire circuit breaks, and all other bulbs go out instantly.

Question details

Q13 of 39 questions

Board
CBSE
Class
Class 10
Subject
Science
Year
2023
Section
Section A
Marks
1
Type
MCQ
Chapter
Electricity
Topic
Electric Current and Circuit
Bloom's level
Understanding
Syllabus topic
Electric current, electric circuit

Spotted a mistake or something unclear?

Tell us and we will fix it.

Frequently asked questions

How many marks does this question carry in CBSE Class 10 Science 2023?

This question carries 1 mark in the CBSE Class 10 Science 2023 examination.

Which chapter does this question come from in Science?

This question is from the chapter "Electricity" in the CBSE Class 10 Science syllabus.

What topic does this question cover in Science?

This question covers the topic "Electric Current and Circuit" from CBSE Class 10 Science.

What type of question is this in the CBSE Class 10 Science 2023 paper?

This is a MCQ question from Section A in the CBSE Class 10 Science 2023 paper.