Advertisements
Advertisements
प्रश्न
Why is cooling produced on evaporation of a liquid?
Advertisements
उत्तर
The evaporation of a liquid requires heat. This heat is taken from the surroundings like the body, palm, forehead, or finger and its temperature falls and we feel cool.
APPEARS IN
संबंधित प्रश्न
How does water kept in an earthen pot (matka) become cool during summer?
Why are we able to sip hot tea or milk faster from a saucer than a cup?
What produces more severe burns, boiling water or steam?
State three factors which affect the rate of evaporation of a liquid.
Why are volatile liquids such as alcohol and spirit stored in tightly closed bottles?
Which produces more severe burns : boiling water or steam ? Why ?
Why does evaporation cool a liquid ?
The scientists now say that there are actually five states of matter A, B, C, D and E. The state A has a fixed volume but no fixed shape. The state B can be compressed very easily by applying pressure and state C has a fixed shape as well as a fixed volume. The state D is a mixture of free electrons and ions whereas state E is named after an Indian scientist and a famous physicist.
- Name the physical states (i) A (ii) B (iii) C (iv) D, and (v) E
- Name one substance belonging to state C which can directly change into vapours on heating. What is this process known as ?
- Name one substance which normally belongs to state B but whose solid form changes directly into gaseous state.
- Name the most common substance belonging to state A.
- Which state of matter makes the sun and other stars to glow ?
Can you suggest a method to collect water from sea water?
When lemon juice is mixed with soda water, they produce brisk effervescence.
