Previous year questions with solutions · 2000 – 2026
| Year | Questions | Papers | Avg / paper | Weightage |
|---|---|---|---|---|
| 2026 | 1 | 2 | 0.5 | 1.11% ▼ 50% vs last year |
| 2025 | 1 | 1 | 1 | 2.22% ▲ 11.1% vs last year |
| 2024 | 2 | 2 | 1 | 2.00% ▲ 100% vs last year |
| 2022 | 1 | 2 | 0.5 | 1.00% ▼ 50% vs last year |
| 2021 | 1 | 1 | 1 | 2.00% ▼ 10% vs last year |
| 2020 | 1 | 1 | 1 | 2.22% ▼ 50% vs last year |
| 2019 | 2 | 1 | 2 | 4.44% ▲ 100% vs last year |
| 2018 | 1 | 1 | 1 | 2.22% ▼ 50% vs last year |
| 2017 | 2 | 1 | 2 | 4.44% ▼ 20% vs last year |
| 2016 | 5 | 2 | 2.5 | 5.56% ▲ 66.7% vs last year |
| 2015 | 3 | 2 | 1.5 | 3.33% ▼ 25% vs last year |
| 2014 | 2 | 1 | 2 | 4.44% ▲ 33.3% vs last year |
| 2013 | 3 | 2 | 1.5 | 3.33% ▼ 11.1% vs last year |
| 2012 | 3 | 2 | 1.5 | 3.75% ▲ 1.2% vs last year |
| 2010 | 3 | 2 | 1.5 | 3.70% ▼ 9.3% vs last year |
| 2009 | 2 | 1 | 2 | 4.08% ▲ 91.8% vs last year |
| 2008 | 1 | 1 | 1 | 2.13% ▼ 50% vs last year |
| 2007 | 2 | 1 | 2 | 4.26% ▲ 112.8% vs last year |
| 2006 | 1 | 1 | 1 | 2.00% ▼ 6% vs last year |
| 2005 | 1 | 1 | 1 | 2.13% ▼ 2.1% vs last year |
| 2004 | 1 | 1 | 1 | 2.17% ▲ 13% vs last year |
| 2003 | 1 | 1 | 1 | 1.92% ▼ 81.9% vs last year |
| 2002 | 5 | 1 | 5 | 10.64% ▲ 421.3% vs last year |
| 2001 | 1 | 1 | 1 | 2.04% ▼ 54.1% vs last year |
| 2000 | 2 | 1 | 2 | 4.44% |
The temperature of a metallic sphere of radius R is increased by a small amount T. If the linear coefficient of thermal expansion of the metal is , the approximate increase in the volume of the sphere is:
Three identical heat conducting rods are connected in series as shown in the figure. The rods on the sides have thermal conductivity 2K while that in the middle has thermal conductivity K. The left end of the combination is maintained at temperature 3T and the right end at T. The rods are thermally insulated from outside. In steady state, temperature at the left junction is T1 and that at the right junction is T2. The ratio T1/T2 is [figure]
A metallic bar of Young's modulus, 0.5 1011 N m-2 and coefficient of linear thermal expansion 10-5 -1, length 1 m and area of cross-section 10-3 m2 is heated from 0 to 100 without expansion or bending. The compressive force developed in it is :
Given below are two statements: One is labelled as Assertion (A) and the other is labelled as Reason (R). In the light of the above statements, choose the correct answer from the options given below.
Two rods one made of copper and other made of steel of same length and same cross sectional area are joined together. The thermal conductivity of copper and steel are 385 J s-1 K-1 m-1 and 50 J s-1 K-1 m-1 respectively. The free ends of copper and steel are held at 100 and 0 respectively. The temperature at the junction is, nearly :
A cup of coffee cools from 90 to 80 in t minutes, when the room temperature is 20 . The time taken by a similar cup of coffee to cool from 80 to 60 at a room temperature same at 20 is :
The quantities of heat required to raise the temperature of two solid copper spheres of radii r1 and r2 (r1 = 1.5r2) through 1 K are in the ratio :
A copper rod of 88 cm and an aluminium rod of unknown length have their increase in length independent of increase in temperature. The length of aluminium rod is : ( Cu = 1.7 10-5 K-1 and Al = 2.2 10-5 K-1)
The power radiated by a black body is P and it radiates maximum energy at wavelength, 0. If the temperature of the black body is now changed so that it radiates maximum energy at wavelength 34 0, the power radiated by it becomes nP. The value of n is
Two rods A and B of different materials are welded together as shown in figure. Their thermal conductivities are K1 and K2. The thermal conductivity of the composite will be [figure]
A spherical black body with a radius of 12 cm radiates 450 watt power at 500 K. If the radius were halved and the temperature doubled, the power radiated in watt would be
Coefficient of linear expansion of brass and steel rods are 1 and 2. Lengths of brass and steel rods are l1 and l2 respectively. If (l2 - l1) is maintained same at all temperatures, which one of the following relations holds good?
A piece of ice falls from a height h so that it melts completely. Only one-quarter of the heat produced is absorbed by the ice and all energy of ice gets converted into heat during its fall. The value of h [Latent heat of ice is 3.4 105 J/kg and g = 10 N/kg]
A black body is at a temperature of 5760 K. The energy of radiation emitted by the body at wavelength 250 nm is U1, at wavelength 500 nm is U2 and that at 1000 nm is U3. Wien's constant, b = 2.88 106 nm K. Which of the following is correct?
Two identical bodies are made of a material for which the heat capacity increases with temperature. One of these is at 100 , while the other one is at 0 . If the two bodies are brought into contact, then, assuming no heat loss, the final common temperature is
A body cools from a temperature 3T to 2T in 10 minutes. The room temperature is T. Assume that Newton's law of cooling is applicable. The temperature of the body at the end of next 10 minutes will be
The value of coefficient of volume expansion of glycerin is 5 10-4 K-1. The fractional change in the density of glycerin for a rise of 40 C in its temperature, is
The two ends of a metal rod are maintained at temperatures 100 and 110 . The rate of heat flow in the rod is found to be 4.0 J/s. If the ends are maintained at temperatures 200 and 210 , the rate of heat flow will be
On observing light from three different stars P, Q and R, it was found that intensity of violet colour is maximum in the spectrum of P, the intensity of green colour is maximum in the spectrum of R and the intensity of red colour is maximum in the spectrum of Q. If TP, TQ and TR are the respective absolute temperatures of P, Q and R, then it can be concluded from the above observations that
Steam at 100 C is passed into 20 g of water at 10 C. When water acquires a temperature of 80 C, the mass of water present will be [Take specific heat of water = 1 cal g-1 C-1 and latent heat of steam = 540 cal g-1]
Certain quantity of water cools from 70 C to 60 C in the first 5 minutes and to 54 C in the next 5 minutes. The temperature of the surroundings is
A piece of iron is heated in a flame. It first becomes dull red then becomes reddish yellow and finally turns to white hot. The correct explanation for the above observation is possible by using
Two metal rods 1 and 2 of same lengths have same temperature difference between their ends. Their thermal conductivities are K1 and K2 and cross sectional areas A1 and A2, respectively. If the rate of heat conduction in 1 is four times that in 2, then
The density of water at 20 is 998 kg/m3 and at 40 is 992 kg/m3. The coefficient of volume expansion of water is
A slab of stone of area 0.36 m2 and thickness 0.1 m is exposed on the lower surface to steam at 100 . A block of ice at 0 rests on the upper surface of the slab. In one hour 4.8 kg of ice is melted. The thermal conductivity of slab is (Given latent heat of fusion of ice = 3.36 105 J kg-1)
If the radius of a star is R and it acts as a black body, what would be the temperature of the star, in which the rate of energy production is Q?
Liquid oxygen at 50 K is heated to 300 K at constant pressure of 1 atm. The rate of heating is constant. Which one of the following graphs represents the variation of temperature with time ?
A cylindrical metallic rod in thermal contact with two reservoirs of heat at its two ends conducts an amount of heat Q in time t. The metallic rod is melted and the material is formed into a rod of half the radius of the original rod. What is the amount of heat conducted by the new rod, when placed in thermal contact with the two reservoirs in time t?
The total radiant energy per unit area, normal to the direction of incidence, received at a distance R from the centre of a star of radius r, whose outer surface radiates as a black body at a temperature T K is given by