Advertisements
Advertisements
प्रश्न
Explain, why do sandy soils, get heated up quickly as compared to wet soils?
Advertisements
उत्तर
The specific heat capacity of sand is about five times less than water. Thus,when sun shines equally on sandy soil and wet soil, the sandy soil gets heated up rapidly as compared to wet soil. It is because water absorbs large amount of heat energy, but its temperature does not rise sufficiently.
संबंधित प्रश्न
In an experiment on the specific heat of a metal, a 0.20 kg block of the metal at 150 °C is dropped in a copper calorimeter (of water equivalent 0.025 kg) containing 150 cm3 of water at 27 °C. The final temperature is 40 °C. Compute the specific heat of the metal. If heat losses to the surroundings are not negligible, is your answer greater or smaller than the actual value for the specific heat of the metal?
The temperature of 170 g of water at 50°C is lowered to 5°C by adding a certain amount of ice to it. Find the mass of ice added.
Given: Specific heat capacity of water = 4200 J kg-1 °C-1 and specific latent heat of ice = 336000 J kg-1.
Name and state the principle used to measure the specific heat capacity of a substance.
Read the following paragraph and answer the questions.
|
If heat is exchanged between a hot and cold object, the temperature of the cold object goes on increasing due to gain of energy and the temperature of the hot object goes on decreasing due to loss of energy. The change in temperature continues till the temperatures of both the objects attain the same value. In this process, the cold object gains heat energy and the hot object loses heat energy. If the system of both the objects is isolated from the environment by keeping it inside a heat resistant box (meaning that the energy exchange takes place between the two objects only), then no energy can flow from inside the box or come into the box. |
- Heat is transferred from where to where?
- Which principle do we learn about from this process?
- How will you state the principle briefly?
- Which property of the substance is measured using this principle?
Specific heat capacity of a substance A is 3.8 J g-1 K-1 and of substance B is 0.4 J g-1 k-1. Which substance is a good conductor of heat? How did you arrive at your conclusion?
Explain, why does a wise farmer water his fields, if forecast is forst?
Read the passage and answer the questions based on it.
If heat is exchanged between a hot and cold object, the temperature of the cold object goes on increasing due to gain of energy and the temperature of the hot object goes on decreasing due to loss of energy. The change in temperature continues till the temperatures of both objects attain the same value. In this process, the cold object gains heat energy and the hot object loses heat energy. If the system of both the objects is isolated from the environment by keeping it inside a heat-resistant box then no energy can flow from inside the box or come into the box. In this situation, we get the following principle.
Heat energy lost by the hot object = Heat energy gained by the cold object. This is called the ‘Principle of heat exchange’.
- Where does heat transfer take place?
- In such a situation which principle of heat do you perceive?
- How can this principle be explained in short?
- Which property of the substance is measured using this principle?
A diatomic gas undergoes adiabatic change. Its pressure 'P' and temperature 'T' are related as p ∝ Tx, where x is ______.
Why is water used as a coolant in radiators of a car?
Match the following
| 1. | Specific heat capacity | a. | Dewar bottle |
| 2. | Calorimeter | b. | Lavoisier and Simon |
| 3. | Vacuum flask | c. | J Kg-1 K-1 |
| 4. | Ice – calorimeter | d. | Heat capacity |
