COMEDK UGET 2025 Heat and Thermodynamics Practice Questions with Solutions

COMEDK UGET 2025 Heat and Thermodynamics Practice Questions with Solutions: Heat and Thermodynamics covers a high weightage in the COMEDK UGET 2025 Physics syllabus . COMEDK UGET Heat and Thermodynamics practice questions cover various important topics such as First Law of Thermodynamics, Thermal Expansion of Solids, Liquids and Gases and their Specific Heat etc. With an aggregate weightage of 13-20%, the chapter is expected to cover around 8-12 questions in the upcoming COMEDK 2025 exam. As known, the exam syllabus includes topics from the 11th and 12th standards, so you are strongly advised to solve COMEDK UGET Heat and Thermodynamics sample questions during preparation and revision. Doing this will help you in getting acquainted with the exam pattern, question types, their weightage, and much more. The practice questions will also familiarize you with the type of questions that are repeated in the exams. In this article, we will be discussing the COMEDK UGET 2025 Heat and Thermodynamics practice questions with solutions, attempting which, you can increase your chances of success in the examination.

Also Check - Do or Die Chapters for COMEDK UGET 2025 Physics

Quick Links:

COMEDK UGET 2025 Heat and Thermodynamics Important Topics

The chapter on Heat and Thermodynamics includes a number of sub topics such as Thermal Expansion of Solids, Thermodynamic Processes, Second Law of Thermodynamics etc. You should know that questions in the COMEDK UGET 2025 exam will be based on these topics. Hence, you are required to pay attention to these topics. Find the list of COMEDK UGET 2025 Heat and Thermodynamics sub topics for exam preparation below:-

COMEDK UGET 2025 Heat and Thermodynamics Expected Weightage

As an exam taker of COMEDK UGET, you must be aware of the weightage along with the total number of questions that the topic of Heat and Thermodynamics will bear. By knowing this, you will be able to prepare accordingly. The table below holds the gist of the COMEDK UGET Heat and Thermodynamics expected weightage along with the expected number of topics:-

Also Check - COMEDK Chapter Wise PYQs for Physics

Quick Links:

COMEDK UGET 2025 Heat and Thermodynamics Practice Questions with Solutions

Consistently practicing COMEDK UGET Heat and Thermodynamics sample questions can significantly enhance your exam preparation. By working through COMEDK UGET 2025 Heat and Thermodynamics practice questions with solutions, you can familiarize yourself with potential exam questions, verify correct answers, and understand the step-by-step solutions. Take a look at some of the key COMEDK Heat and Thermodynamics practice questions 2025, carefully selected by experts from past exam papers:-

Q1. The coefficient of volume expansion of glycerine is 49 x 10-5 K-1. The percentage change in its density for a 50℃ rise in temperature is:

a) 3.54

b) 5.24

c) 4.25

d) 2.45

Correct answer - d) 2.45

Explanation:

The coefficient of volume expansion (????) is given as 49 x 10-5 K ^-1 . The formula to determine the change in volume due to change in volume due to thermal expansion is:

ΔV = V ???? ΔT

Here:

ΔV is the change in volume

V is the original volume

???? is the co-efficient of volume expansion

ΔT is the change in temperature

Given that the temperature change in (ΔT) is 50℃, we have:

ΔV = V . (49 x 10 ^-5 K ^-1 ) . 50

ΔV = V . (49 x 10-5 x 50)

ΔV = V . (2450 x 10-5)

ΔV = V.0.0245

This indicates that the volume increases by 2.45%. Since density (℘) is inversely proportional to volume (V), a 2.45% increase in volume will result in a 2.45% decrease in density.

Thus, the percentage change in density is 2.45%. Hence, the correct option is:

Option D: 2.45

Q2. The latent heat of vaporisation of water is 2240 J. If the work done in the process of vaporisation of 1g is 168 J, the increase in internal energy is:

a) 1408 J

b) 2702 J

c) 2208 J

d) 2408 J

Correct answer - b) 2702 J

Explanation: The latent heat of vaporisation, also known as the enthalpy of vaporisation, reflects the energy required to transform a substance from a liquid phase to a gas phase without changing its temperature. According to the first law of thermodynamics, the change in internal energy (ΔU) during the process of vaporisation can be calculated using the formula:

ΔU = Q-W

Where:

Q is the heat added (latent heat of vaporisation)

W is the work done in the process.

In this scenario:

The latent heat of vaporisation (Q) is 2240 J

The work done (W) is 168 J

Substituting these values into the equation, we get:

ΔU = 2240 J - 168 J

Therefore,

ΔU = 2072 J

Hence, the increase in internal energy is:

Option B: 2072 J

Q3. The gases carbon monoxide (CO) and nitrogen at the same temperature have kinetic energies E ¹ and E ² , respectively. Then:

a) E ¹ = E ²

b) E ¹ > E ²

c) E ¹ < E ²

d) None of these

Correct answer - a) E ¹ = E ²

Explanation: The gases carbon monoxide (CO) and nitrogen (N2) are diatomic, so both have equal kinetic energy 5/2KT, ie, E ¹ = E ²

Q4. If 150J of heat is added to a system and the work done by the system is 110 J, then the change in internal energy will be:

a) 40 J

b) 110 J

c) 150 J

d) 260 J

Correct answer - a) 40 J

Explanation: From the first law of thermodynamics, if an amount of heat Q is given to a system, a part of it is used in increasing the internal energy ΔU of the system and the rest in doing work W by the system.

Hence Q = ΔU + W

→ ΔU = Q-W → ΔU = 150 - 110

→ 40 J

Q5. The average kinetic energy of a molecule in air at room temperature of 20℃:

a) 6 x 10 ^-22 J

b) 7.06 x 10 ^-21 J

c) 6.07 x 10 ^-21 J

d) 6.70 x 10 ^-21 J

Correct answer - c) 6.07 x 10 ^-21 J

Explanation:

The average molecular kinetic energy is expressed as:

K̅ = ½ mv ² = 3/2 kT

Given, T = 20℃ = 20 + 273 = 293K

K = 1.38 x 10-23 J/K = Boltzmann’s constant

Substituting all the values, we get:

K̅ = 3/2 x 1.38 x 10-23 x 293

= 6.07 x 10-21 J

While solving COMEDK Heat and Thermodynamics practice questions, you must keep track of time since the actual exam is time-bound. Set a timer, assess how long it takes to solve each question, use shortcut tricks from COMEDK 2025 Physics formula sheet to easily attempt the questions, to improve speed and time management skills.

Related Articles