Advertisements
Advertisements
Question
Explain, why does a wise farmer water his fields, if forecast is forst?
Advertisements
Solution
The frost can seriously damage the leaves and fruit of plants. When a farmer waters his fields, during, night, this water gives large amount of heat energy, because 1 g of water will liberate 4.2 J of energy for every 1°C fall in temperature. Thus, the air around the field is saturated with heat energy and its temperature does not fall below 0°C. Thus, no frost is formed.
RELATED QUESTIONS
Heat energy is supplied at a constant rate to 100g of ice at 0 °C. The ice is converted into water at 0° C in 2 minutes. How much time will be required to raise the temperature of water from 0 °C to 20 °C? [Given: sp. heat capacity of water = 4.2 J g-1 °C-1, sp. latent heat of ice = 336 J g-1].
A liquid X has the maximum specific heat capacity and is used as a coolant in Car Radiators. Name the liquid X.
Name the S.I. unit of heat.
Give three reasons for the increase of green house gases.
How will global warming disturb the ecological balance?
State the condition for the flow of heat energy from one body to another.
m kg of a substance of specific heat capacity s J/kg °C is heated so that its temperature rises from θ1°C to θ2°C. Write down the expression for the heat Q supplied.
The farmers fill their fields with water in winter. Give reason.
For a gas `"R"/"C"_"v" = 0.4,` where 'R' is the universal gas constant and 'Cv' is molar specific heat at constant volume. The gas is made up of molecules which are ______.
Two metals A and B have specific heat capacities in the ratio 2:3. If they are supplied same amount of heat then
Which metal piece will have greater mass if the rise in temperature is the same for both metals?
