Properties of Solids & Liquids (NEET (NTA)National Eligibility cum Entrance Test (Medical) Physics): Questions 157  159 of 190
Visit this page to view all the question topics
To view these problems with solutions proceed here and click "Subscribe Now".
Question number: 157
» Properties of Solids & Liquids » Heat Transfer » Radiation
Question
Two bodies A and B have thermal emissivity of 0.01 and 0.81 respectively. The outer surface areas of the two bodies are the same. The two bodies emit total radiant power at the same rate. The wavelength λ _{B} corresponding to maximum spectral radiance in the radiation from B is shifted from the wavelength corresponding to maximum spectral radiance in the radiation from A, by 1.00 µm. If the temperature of A is 5802 K
(1) The temperature of B is 1934 K
(2) λ _{B} = 1.5 μm
(3) The temperature of B is 11604 K
(4) The temperature of B is 2901 K
Select the correct answers and mark it according to the following codes:
Choices
Choice (4)  Response  

a.  1 and 3 are correct 

b.  1 and 2 are correct 

c.  1,2 and 3 are correct 

d.  2 and 4 are correct 

To view these problems with solutions proceed here and click "Subscribe Now".
Question number: 158
» Properties of Solids & Liquids » Latent Heat
Question
A stationary object at 4° C and weighing 3.5 kg falls from a height of 2000 m on a snow mountain at 0° C. If the temperature of the object just before hitting the snow is 0°C and the object comes to rest immediately? (g = 10 m/s ^{2} and latent heat of ice = 3.5 × 10 ^{5} joule/sec), then the object will melt
Choices
Choice (4)  Response  

a.  2 gm of ice 

b.  2 kg of ice 

c.  20 gm of ice 

d.  200 gm of ice 

To view these problems with solutions proceed here and click "Subscribe Now".
Question number: 159
» Properties of Solids & Liquids » Heat Transfer » Radiation
Question
A body cools from 90° C to 50° C in 10 minutes. If the room temperature is 25° C and assuming Newton’s law of cooling to hold good, the temperature of the body at the end of the next 10 minutes will be
Choices
Choice (4)  Response  

a.  56.40° C 

b.  34.61° C 

c.  46.75° C 

d.  42.85° C 

To view these problems with solutions proceed here and click "Subscribe Now".