MEDIUM
Earn 100

Why do we see water droplets on the outer surface of glass in cold water?

Important Questions on Matter in our Surroundings

MEDIUM
Read the following and select the correct option.
Statement (a) : When we pour little petrol on our palm, it causes the palm to feel cool.
Reason (b) : Particles of petrol evaporate using the energy from our palm which causes the palm to feel cool. 
EASY
The water kept in an earthen pot(matka) become cool during summer by which process?
EASY

Let T = Temperature; H = Humidity and v = Wind speed
Which of the following are the best suited conditions for drying up of clothes?

MEDIUM

The vapour content in the air is measured using a physical quantity called 

EASY
A person takes hot coffee by pouring it into the saucer when he is in a hurry because he knows that:
EASY
"Spirit kept in an open watch glass is converted into gaseous state even at room temperature". Explain.
MEDIUM
Why does ethanol evaporate faster than water?
MEDIUM

Define evaporation. Give an example that indicates that evaporation is an endothermic process.

MEDIUM

Define:

A. evaporation

B. sublimation

MEDIUM
Why does our palm feel cold when we put some acetone or petrol or perfume on it?
HARD
Describe the factors which affect evaporation.
MEDIUM

Why does our palm feel cold when we put some acetone, ethyl alcohol, petrol or perfume on it?

MEDIUM
Why is it that wet clothes dry quickly in the sun than in the shade? 
MEDIUM

Why does water evaporate faster in a Petri dish than in a test tube?

MEDIUM

What are the factors which affect the rate of evaporation?

MEDIUM
Why does it take longer time for the evaporation process on a rainy day?
MEDIUM

Why do we feel cool under a fan when we perspire?

MEDIUM
Is evaporation an endothermic or exothermic process? Give one example to support your answer.
EASY

Which of the following conditions will increase the evaporation of water?

MEDIUM
Why does water get cooled in an earthen pot?