Learn

Saturday, 31 October

JEE Main 2021 · ChemistryNumerical answerNumerical valueMediumMulti-step

JEE Main 4 August 2021, Shift 1, Chemistry Q53

Question 53 of 90 in this shift, Chemistry question 23 of 30, Section B.

A lead bullet weighing 18 g and travelling with a velocity of 500 m/s−1^{-1} is embedded in a wooden block weighing 1 kg. If both the block and the bullet were initially at 25°C, the final temperature of the block containing the bullet is ________ °C. (Nearest integer) [Assume no heat is lost to the surroundings, heat capacity of wood and lead are 0.5 kcal kg−1^{-1} K−1^{-1}, 0.03 kcal kg−1^{-1} K−1^{-1} respectively.]

Official answer

26

NTA final key.

Chapter
Thermodynamics (Chemistry)
Topic
First Law of Thermodynamics
Idea tested
Mechanical Energy to Internal Energy Conversion

Same topic in other shifts

All First Law of Thermodynamics questions
  1. 2 Apr 2026, Shift 1 · Q47A vessel contains 0.15 m30.15\ \mathrm{m^3} of a gas at pressure 88 bar and temperature 140 ∘140\ ^\circC with cp=3Rc_p=3R and cv=2Rc_v=2R. It is…MediumNumerical value
  2. 2 Apr 2026, Shift 2 · Q485 moles of unknown gas is heated at constant volume from 10°C to 20°C. The molar specific heat of this gas at constant pressure cp=8c_p = 8…MediumNumerical value
  3. 5 Apr 2026, Shift 1 · Q33Consider the following statements: A. Zeroth law of thermodynamics gives concept of temperature B. First law of thermodynamics gives…MediumOther
  4. 6 Apr 2026, Shift 1 · Q50A certain gas is isothermally compressed to (13)rd\left(\frac{1}{3}\right)^{\mathrm{rd}} of its initial volume (V0=3V_0=3 litre) by applying…MediumNumerical value
  5. 6 Apr 2026, Shift 2 · Q35If 2 mole of an ideal monoatomic gas at temperature TT, is mixed with 6 mole of another ideal monoatomic gas at temperature 2T2T then the…EasySingle correct
  6. 8 Apr 2026, Shift 2 · Q35One mole of diatomic gas having rotational modes only is kept in a cylinder with a piston system. The cross-section area of the cylinder…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.