PPT on Heat (NTSE Science) - Class 8 PDF Download

 Page 1


NTSE  Science 
HEAT
Professor. Santhosh
Managing Director & Science Educator 
Aksharam Educational Academy 
Page 2


NTSE  Science 
HEAT
Professor. Santhosh
Managing Director & Science Educator 
Aksharam Educational Academy 
1) Hot and cold :-
In our daily life we come across a number of objects.
Some of them are hot and some of them are cold.
Eg :- Tea is hot and ice is cold.
Some objects are hotter than others and some are colder  
than others.
We often decide which object is hotter than the other by  
touching the objects.
We cannot always rely on our sense of touch to decide  
how hot or how cold an object is.
The hotness of an object is measured by its temperature.
Temperature :- is a measure of the degree of hotness of an  
object.
Temperature is measured by a device called thermometer.
Page 3


NTSE  Science 
HEAT
Professor. Santhosh
Managing Director & Science Educator 
Aksharam Educational Academy 
1) Hot and cold :-
In our daily life we come across a number of objects.
Some of them are hot and some of them are cold.
Eg :- Tea is hot and ice is cold.
Some objects are hotter than others and some are colder  
than others.
We often decide which object is hotter than the other by  
touching the objects.
We cannot always rely on our sense of touch to decide  
how hot or how cold an object is.
The hotness of an object is measured by its temperature.
Temperature :- is a measure of the degree of hotness of an  
object.
Temperature is measured by a device called thermometer.
Feeling water in three mugs
Hot
Water  
Cold 
water  
Mixed  
Page 4


NTSE  Science 
HEAT
Professor. Santhosh
Managing Director & Science Educator 
Aksharam Educational Academy 
1) Hot and cold :-
In our daily life we come across a number of objects.
Some of them are hot and some of them are cold.
Eg :- Tea is hot and ice is cold.
Some objects are hotter than others and some are colder  
than others.
We often decide which object is hotter than the other by  
touching the objects.
We cannot always rely on our sense of touch to decide  
how hot or how cold an object is.
The hotness of an object is measured by its temperature.
Temperature :- is a measure of the degree of hotness of an  
object.
Temperature is measured by a device called thermometer.
Feeling water in three mugs
Hot
Water  
Cold 
water  
Mixed  
Clinical thermometers
The thermometer that measures our body
temperature is called a clinical thermometer.
What is 
filled in 
side? 
Page 5


NTSE  Science 
HEAT
Professor. Santhosh
Managing Director & Science Educator 
Aksharam Educational Academy 
1) Hot and cold :-
In our daily life we come across a number of objects.
Some of them are hot and some of them are cold.
Eg :- Tea is hot and ice is cold.
Some objects are hotter than others and some are colder  
than others.
We often decide which object is hotter than the other by  
touching the objects.
We cannot always rely on our sense of touch to decide  
how hot or how cold an object is.
The hotness of an object is measured by its temperature.
Temperature :- is a measure of the degree of hotness of an  
object.
Temperature is measured by a device called thermometer.
Feeling water in three mugs
Hot
Water  
Cold 
water  
Mixed  
Clinical thermometers
The thermometer that measures our body
temperature is called a clinical thermometer.
What is 
filled in 
side? 
2) Measuring temperature :-
The thermometer that measures the temperature of our  
body is called clinical thermometer.
A clinical thermometer has a long narrow glass tube. It has  
a bulb at one end containing mercury. It has a scale called  
celsius scale marked in 
0
C (degree celsius). A clinical  
thermometer reads temperature from 35 
0
C to 42 
0
C.The  
clinical thermometer has a small kink near the bulb to  
prevent the mercury level from falling down.
The normal temperature of the human body is 37
0
C.
mercury
Clinical thermometer
kink
kink