A body cools down from 80∘C to 70∘C
1. | less than 5 minutes. |
2. | equal to 5 minutes. |
3. | more than 5 minutes. |
4. | can't say anything as the temperature of the surroundings is not known. |
If λm is the wavelength, corresponding to which the radiant intensity of a block is at its maximum and its absolute temperature is T, then which of the following graphs correctly represents the variation of T?
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Heat capacity is equal to the product of:
1. mass and gas constant
2. mass and specific heat
3. latent heat and volume of water
4. mass and Avogadro number
When a block of iron floats in Hg at 0°C, a fraction K1 of its volumen= is submerged, while at temperature of 60°C a fraction K2 is seen to be submersed. If the coefficient of volume expansion of iron is γFe and that of mercury is γHg, then the ratio K1K2 can be expressed as:
1. 1+60γFe1+60γHg
2. 1-60γFe1+60γHg
3. 1+60γFe1-60γHg
4. 1+60γHe1-60γFe
Hot water cools from 60°C to 50°C in first 10 minutes and from 50°C to 42°C in next 10 minutes. The temperature of surrounding is :
1. 5° C
2. 10° C
3. 15° C
4. 20°C
A pendulum clock runs faster by 5 s per day at 20∘C and goes slow by 10 s per day at 35∘C. It shows the correct time at a temperature of:
1. 27.5∘C
2. 25∘C
3. 30∘C
4. 33∘C
A constrained steel rod of length l, area of cross-section A, Young's modulus Y and coefficient of linear expansion α is heated through t∘C. The work that can be performed by the rod when heated is:
1. (YAαt)(lαt)
2. 12(YAαt)(lαt)
3. 12(YAαt)12(lαt)
4. 2(YAαt)(lαt)
The temperature of a body on Kelvin scale is found to be X K. When it is measured by a Fahrenheit thermometer, it is found to be X0F. Then X is
1. 301.25
2. 574.25
3. 313
4. 40
A temperature of 100∘F (Fahrenheit scale) is equal to T K (Kelvin scale). The value of T is:
1. 310.9
2. 37.8
3. 100
4. 122.4