Two conducting wires of the same material and of equal lengths and equal diameters are first connected in parallel and then in series in a circuit across the same potential difference. The ratio of heat produced in parallel and series combinations is

This question was previously asked in
NDA-I (GAT) Official Paper (Held On: 13 Apr, 2025)
View all NDA Papers >
  1. 2:1
  2. 4:1
  3. 1:2
  4. 1:4

Answer (Detailed Solution Below)

Option 2 : 4:1
Free
UPSC NDA 01/2025 General Ability Full (GAT) Full Mock Test
6 K Users
150 Questions 600 Marks 150 Mins

Detailed Solution

Download Solution PDF

Calculation:

Let the resistance of each wire be R.

Parallel Combination:

Equivalent resistance, Rparallel = R / 2

Heat produced, Hparallel ∝ 1 / Rparallel

⇒ Hparallel ∝ 1 / (R / 2) = 2 / R

Series Combination:

Equivalent resistance, Rseries = 2R

Heat produced, Hseries ∝ 1 / Rseries

⇒ Hseries ∝ 1 / (2R)

Ratio of Heat Produced:

Ratio = Hparallel : Hseries

⇒ Ratio = (2 / R) : (1 / (2R))

⇒ Ratio = 4 : 1

∴ The ratio of heat produced in parallel and series combinations is 4:1.

Latest NDA Updates

Last updated on Jul 8, 2025

->UPSC NDA Application Correction Window is open from 7th July to 9th July 2025.

->UPSC had extended the UPSC NDA 2 Registration Date till 20th June 2025.

-> A total of 406 vacancies have been announced for NDA 2 Exam 2025.

->The NDA exam date 2025 has been announced. The written examination will be held on 14th September 2025.

-> The selection process for the NDA exam includes a Written Exam and SSB Interview.

-> Candidates who get successful selection under UPSC NDA will get a salary range between Rs. 15,600 to Rs. 39,100. 

-> Candidates must go through the NDA previous year question paper. Attempting the NDA mock test is also essential. 

Get Free Access Now
Hot Links: happy teen patti teen patti real cash game teen patti gold old version teen patti lotus