HEAT - POST -10

Heat -Post 10

 

 CONVECTION part II

 

 

 

 Well boys, we have learnt about  Convection. During today's blog lesson we will look into another experiment based on  Convection currents in air and its practical application.

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The link below provides a recap to  convection currents in  liquids and moves on to explain convection currents in Air.


          https://www.youtube.com/watch?v=0CxkdJeqNfM





Click on the link below if you would like a recap of the experiment   that was taught yesterday which explains convection currents in liquids ( Round Bottomed flask experiment with Potassium per mangnate)

https://youtu.be/0BdRaWFR2IM

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The link below explains how Land and Sea Breezes occur in Coastal Areas.

https://youtu.be/DzwnlzmW-Z0

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The  link below explains  Land and Sea Breezes and other practical applications of Convection Currents. ( Why ventilators are placed at a height and windows at a lower level, a chimney in a chemistry laboratory )

https://youtu.be/7MOW7TouBJ0






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 I do hope after the above activity you are fairly  familiar with the concept of convection currents.
Some applications of convection currents are listed below and before  reading the answer spend a few moments by thinking of the solution or reason for the same yourself.


Q24)Why  are ventilators   ( room ventilators ) placed  at a height. ( closer towards the ceiling)

Ans) Warm air being lighter rises up and leaves the room through ventilators provided near the ceiling . To compensate for the space left in the room left by the warm air,  fresh air from outside enters the room through windows and doors.( As happened in the flask experiment , the colder air becomes warm , becomes lighter and rises up and fresh air from outside comes to take its place. The convection currents so set in the air helps to keep the room cool.)
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  Click on the link below which explains how land and sea breezes take place. (  This concept was introduced to you in class 4 in all probability )

             https://www.youtube.com/watch?v=DzwnlzmW-Z0

 Sea breeze

    LAND BREEZE



Land and Sea Breeze
 You must have learned about land and sea breezes  in class 4 but did you know that it was based on the concept of convection current. 

DO THE QUESTIONS GIVEN IN GREEN IN YOUR NOTEBOOK

 Q 25) Explain how a SEA BREEZE takes place.

Ans) During the day, the land warms up more than the sea. The air over the land becomes warm and rises up. To take its place, cold air from the sea starts blowing towards the land. The convection current from the sea to land is known as sea breeze.
 Q26) Explain how a land breeze takes pace.


After sunset, land loses heat faster than the sea. As a result, the air over the sea is warmer at night. The air over the sea being warmer rises and cooler air from the land rushes to take its place. The convection current from the land to the sea is known as land breeze.
Q27) Draw neat labelled diagrams of land and sea breeze.

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 By the end of today's lesson you should be able to

•  explain  Convection Currents

• Draw a neat labelled  Diagram that explains how a Sea  Breeze takes place
• Draw a neat labelled Diagram that explains how a Land Breeze occurs
• Explain the  occurence of Land and Sea Breezes
• Reason why ventilators and windows are placed where they are.

           

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