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प्रश्न
A solid metal weighing 150 g melts at its melting point of 800 °C by providing heat at the rate of 100 W. The time taken for it to completely melt at the same temperature is 4 min. What is the specific latent heat of fusion of the metal?
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उत्तर
Given:
m = 150g = 150 × 10(-3) kg = 0.15 kg
Power (P) = 100W,
Time (t) = 4 min = 4 × 60 sec
The amount of heat supplied in 4 min
Heat energy (Q) = 100 × 4 × 60 = 24000 J
This heat energy is used in melting.
Let L be the latent specific heat.
∴ L = `"Q"/"m"`
∴ L = `24000/0.15`
= 1.6 × 105 J kg-1
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संबंधित प्रश्न
Given below are observations on molar specific heats at room temperature of some common gases.
| Gas |
Molar specific heat (Cv) (cal mol–1 K–1) |
| Hydrogen | 4.87 |
| Nitrogen | 4.97 |
| Oxygen | 5.02 |
| Nitric oxide | 4.99 |
| Carbon monoxide | 5.01 |
| Chlorine | 6.17 |
The measured molar specific heats of these gases are markedly different from those for monatomic gases. Typically, molar specific heat of a monatomic gas is 2.92 cal/mol K. Explain this difference. What can you infer from the somewhat larger (than the rest) value for chlorine?
What do you understand by the following statements:
The heat capacity of the body is 60JK-1.
Name and state the principle used to measure the specific heat capacity of a substance.
Write the approximate values of the specific latent heat of fusion of ice.
1 kg of water freezes to form ice at 0°C. What amount of heat is withdrawn?
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What could be the final temperature of a mixture of 100 g of water at 90 °C and 600g of water at 20°C.
At same temperature and pressure of an ideal gas, ____________.
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The specific heat capacity of ______ is maximum.
