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JEE Main 2023 · PhysicsMultiple choiceSingle correctMediumCalculation

JEE Main 12 April 2023, Shift 1, Physics Q37

Question 37 of 90 in this shift, Physics question 7 of 30, Section A.

A body cools from

80^\circ

C to

60^\circ

C in 5 minutes. The temperature of the surrounding is

20^\circ

C. The time it takes to cool from

60^\circ

C to

40^\circ

C is:

(1) $\frac{25}{3}$ s
(2) $500$ sOfficial answer
(3) $450$ s
(4) $420$ s

Official answer

Option 2

NTA final key.

Chapter: Thermal Properties of Matter
Topic: Thermal Radiation
Idea tested: Average Temperature Method for Newton's Law of Cooling

Same idea in other shifts

Asked 2× in all

3 Sep 2020, Shift 2 · Q6A metallic sphere cools from $50^\circ$ C to $40^\circ$ C in 300 s. If atmospheric temperature around is $20^\circ$ C, then the sphere's…MediumSingle correct

Question text from the official JEE Main paper published by NTA; answer from the final answer key. Chapter, topic and idea tags, difficulty and skill are Lumi’s. Lumi analyses 108 of the 174 JEE Main shifts held from 2017 to 2026.