The value of the coefficient of volume expansion of glycerin is \(5\times10^{-4}\) K-1. The fractional change in the density of glycerin for a temperature increase of \(40^\circ \mathrm{C}\) will be:

1. \(0.015\) 2. \(0.020\)
3. \(0.025\) 4. \(0.010\)

Subtopic:  Thermal Expansion |
 83%
Level 1: 80%+
NEET - 2015
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Steam at \(100^{\circ}\mathrm{C}\) is injected into 20 g of \(10^{\circ}\mathrm{C}\) water. When water acquires a temperature of \(80^{\circ}\mathrm{C}\), the mass of water present will be: (Take specific heat of water =1 cal g-1 \(^\circ\)C-1 and latent heat of steam = 540 cal g-1)

1. 24 g 2. 31.5g
3. 42.5 g 4. 22.5 g
Subtopic:  Calorimetry |
 73%
Level 2: 60%+
NEET - 2014
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Liquid oxygen at 50K is heated to 300K 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?

1. 

2. 

3. 

4. 

Subtopic:  Thermal Expansion |
 80%
Level 1: 80%+
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The coefficient of linear expansion of brass and steel are α1 and α2. If we take a brass rod of length l1 and steel rod of length l2 at 0°C, their difference in length l2-l1 will remain the same at a temperature if

1. α1l2=α2l1                                 

2. α1l22=α2l12

3. α12l1=α22l2                                   

4. α1l1=α2l2

Subtopic:  Thermal Expansion |
 80%
Level 1: 80%+
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Heat travels through vacuum by 

1. Conduction                 

2. Convection

3. Radiation                     

4. Both (1) and (2)

Subtopic:  Radiation |
 77%
Level 2: 60%+
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We consider the radiation emitted by the human body. Which of the following statements is true?

(1) The radiation is emitted only during the day.

(2) The radiation is emitted during the summers and absorbed during the winters.

(3) The radiation emitted lies in the ultraviolet region and hence is not visible.

(4) The radiation emitted is in the infra-red region.

Subtopic:  Radiation |
 58%
Level 3: 35%-60%
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Certain substance emits only the wavelengths λ1,λ2,λ3 and λ4 when it is at a high temperature. When this substance is at a colder temperature, it will absorb only the following wavelengths ?

1. λ1                     

2. λ2

3. λ1 and λ2         

4. λ1,λ2,λ3 and λ4

Subtopic:  Radiation |
 86%
Level 1: 80%+
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As compared to the person with white skin, the person with black skin will experience 

1. Less heat and more cold           

2. More heat and more cold

3. More heat and less cold             

4. Less heat and less cold

Subtopic:  Radiation |
 58%
Level 3: 35%-60%
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If between wavelength λ and λ+, eλ and aλ be the emissive and absorptive powers of a body and Eλ be the emissive power of a perfectly black body, then according to Kirchoff's law, which is true ?

1. eλ= aλEλ          

2. eλEλ=aλ

3. eλaλEλ              

4. eλaλEλ = constant

Subtopic:  Radiation |
 57%
Level 3: 35%-60%
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When p calories of heat is given to a body, it absorbs q calories; then the absorbtion power of body will be ?

1. p/q                         

2. q/p

3. p2/q2                     

4. q2/p2

Subtopic:  Radiation | Stefan-Boltzmann Law |
 76%
Level 2: 60%+
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