8.1: Temperature of water in a beaker is 50°C. What is its value in Fahrenheit scale? Ans. (122°F)

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8.2: Normal human body temperature is 98.6°F. Convert it into Celsius scale and Kelvin scale. Ans. (37°C, 310 K)


8.3: Calculate increase in the length of an Aluminum bar 2 m long when heated from 0°C to 20°C. The thermal coefficient of linear expansion of Aluminum is 2.5 ｘ10⁻⁵K⁻¹. Ans. (0.1cm)


8.4 A balloon contains 1.2 m³ air at 15°C. Find its volume at 40°C. Thermal coefficient of volume expansion of air is 3.67ｘ10⁻³K⁻¹. (1.3 m³)


8.5: How much heat is required to increase the temperature of 0.5kg of water from 10°C to 65°C? Ans.  (115500 J)



8.6: An electric heater supplies heat at the rate of 1000 joules per second. How much time is required to raise the temperature of 200g of water from 20°C to 90°C? Ans. (58.8 s)


8.7: How much ice will melt by 50000 J of heat? Latent heat of fusion of ice = 336000 J kg⁻¹. Ans. (150 g)


8.8: Find the quantity of heat needed to melt 100g of ice at -10°C into water at 10°C. Ans(39900 J) 

(Note: Specific heat of ice is 2100 Jkg⁻¹K⁻¹, specific heat of water is 4200 Jkg⁻¹K⁻¹, Latent heat of fusion of ice is 336000 Jkg⁻¹).

8.9: How much heat is required to change 100 g of water at 100°C into steam? (Latent heat of vaporization of water is 2.26 ｘ10⁶  Jkg⁻¹. Ans. (2.26 ｘ 10⁵ J)


8.10: Find the temperature of water after passing 5 g of steam at 100 °C through 500 g of water at 10 °C. Ans. (16.2°C) 

(Note: Specific heat of water is 4200 Jkg-1K⁻¹, Latent heat of vaporization of water is 2.26 ｘ 10⁶ Jkg⁻¹).