Sign in
12thPass logo
New chatPYQ LibraryDoubtsRank report
Sign in to see Recents

Your guest activity stays on this device

Sign in to save progress →
Sign in

Heat and Thermodynamics question

2023 · 11 Apr · Shift 1 · Q52
Guest · filters and generic practice availableBrowsing as a guest · PYQ filters and generic practice are available. Sign in only for personalised features and saved progress.
  1. PYQ Library
  2. /JEE Main
  3. /Physics
  4. /Heat and Thermodynamics
  5. /2023 · 11 Apr · Shift 1 · Q52

Heat and Thermodynamics question

2023 · 11 Apr · Shift 1 · Q52

JEE MainPhysicsHeat and ThermodynamicsMCQ+4 / −1
On a temperature scale 'X\mathrm{X}X', the boiling point of water is 65∘X65^{\circ} \mathrm{X}65∘X and the freezing point is −15∘X-15^{\circ} \mathrm{X}−15∘X. Assume that the X\mathrm{X}X scale is linear. The equivalent temperature corresponding to −95∘X-95^{\circ} \mathrm{X}−95∘X on the Farenheit scale would be:
  1. A
    −148∘F-148^{\circ} \mathrm{F}−148∘F
  2. B
    −48∘F-48^{\circ} \mathrm{F}−48∘F
  3. C
    −63∘F-63^{\circ} \mathrm{F}−63∘F
  4. D
    −112∘F-112^{\circ} \mathrm{F}−112∘F
View written solutionFree

Correct answer: A

  1. Use the fixed points of the linear scale

For the scale XXX:

  • Freezing point of water: 0∘C↔−15∘X0^\circ C \leftrightarrow -15^\circ X0∘C↔−15∘X
  • Boiling point of water: 100∘C↔65∘X100^\circ C \leftrightarrow 65^\circ X100∘C↔65∘X

Since the scale is linear, let X=aC+bX = aC + bX=aC+b

Using C=0C=0C=0: −15=a(0)+b⇒b=−15-15 = a(0) + b \Rightarrow b=-15−15=a(0)+b⇒b=−15

Using C=100C=100C=100: 65=100a−1565 = 100a - 1565=100a−15 100a=80100a = 80100a=80 a=0.8a = 0.8a=0.8

So, X=0.8C−15X = 0.8C - 15X=0.8C−15

  1. Convert −95∘X-95^\circ X−95∘X to Celsius

Given: −95=0.8C−15-95 = 0.8C - 15−95=0.8C−15 0.8C=−800.8C = -800.8C=−80 C=−100∘CC = -100^\circ CC=−100∘C

  1. Convert Celsius to Fahrenheit

Relation: F=95C+32F = \frac{9}{5}C + 32F=59​C+32

Substitute C=−100C=-100C=−100: F=95(−100)+32F = \frac{9}{5}(-100) + 32F=59​(−100)+32 F=−180+32F = -180 + 32F=−180+32 F=−148∘FF = -148^\circ FF=−148∘F

  1. Match with the options

The correct option is: A  (−148∘F)\boxed{A\; (-148^\circ F)}A(−148∘F)​

  1. Comparison with stored answer

Stored correct answer: AAA

Our derived answer also gives AAA, so they agree.

PreviousNext

More from Heat and Thermodynamics

  • Three vessels of equal volume contain gases at the same temperature and pressure. The first vessel contains neon (monoatomic), the second contains chlorine (diatomic) and third contains uranium hexafloride (polyatomic). Arrange these on…2023 · MCQ
  • The Thermodynamic process, in which internal energy of the system remains constant is2023 · MCQ
  • The root mean square speed of molecules of nitrogen gas at 27∘C is approximately : (Given mass of a nitrogen molecule =4.6×10−26 kg and take Boltzmann constant kB​=1.4×10−23JK−1…2023 · MCQ
  • If the r. m.s speed of chlorine molecule is 490 m/s at 27∘C, the r. m. s speed of argon molecules at the same temperature will be (Atomic mass of argon =39.9u, molecular mass of…2023 · MCQ
  • The rms speed of oxygen molecule in a vessel at particular temperature is (1+x5​)21​v, where v is the average speed of the molecule. The value of x will be: ( Take π=722​)…2023 · MCQ
  • The initial pressure and volume of an ideal gas are P 0​ and V 0​. The final pressure of the gas when the gas is suddenly compressed to volume 4V0​​ will be : (Given γ = ratio of specific heats at constant pressure and…2023 · MCQ
  • The mean free path of molecules of a certain gas at STP is 1500 d, where d is the diameter of the gas molecules. While maintaining the standard pressure, the mean free path of the molecules at 373 K is…2023 · MCQ
  • Two plates A and B have thermal conductivities 84 Wm−1 K−1 and 126 Wm−1 K−1 respectively. They have same surface area and same thickness. They are placed in…2023 · Numerical