EASY
7th Foundation
IMPORTANT
Earn 100

A thermos flask is a household item that is used to keep things warm or cold for a long time. What is the use of silvered wall in thermos flask?

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Important Questions on Heat

EASY
7th Foundation
IMPORTANT
NSO Science Olympiad Workbook Grade 7>Chapter 3 - Heat>EXERCISES>Q 11
Which of the following statement(s) is/are incorrect?
(i) Two thin woollen sweaters are warmer than a thick woollen sweater.
(ii) It saves fuel if we cook food in a vessel which is blackened at the bottom and polished from the sides.
(iii) The cable wires between two poles are left loose, because in summers the wires may not break on expanding.
EASY
7th Foundation
IMPORTANT
NSO Science Olympiad Workbook Grade 7>Chapter 3 - Heat>EXERCISES>Q 12

A saucepan is usually made up of two different materials, P and Q. Identify P and Q.

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EASY
7th Foundation
IMPORTANT
NSO Science Olympiad Workbook Grade 7>Chapter 3 - Heat>EXERCISES>Q 13
Which of the following statements is incorrect?
EASY
7th Foundation
IMPORTANT
NSO Science Olympiad Workbook Grade 7>Chapter 3 - Heat>EXERCISES>Q 14

Two glass test tubes are heated from two different places of the test tubes. In which test tube will all the water heat up first?

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EASY
7th Foundation
IMPORTANT
NSO Science Olympiad Workbook Grade 7>Chapter 3 - Heat>EXERCISES>Q 15

A hot liquid is carefully poured into a beaker. The graph shows how its temperature changes as it cools towards room temperature. Which process(es) is/are taking place at region X ?

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EASY
7th Foundation
IMPORTANT
NSO Science Olympiad Workbook Grade 7>Chapter 3 - Heat>EXERCISES>Q 16
Two steel balls P and Q have same readings when measured by thermometers of Celsius readings and Fahrenheit readings respectively. Then,
EASY
7th Foundation
IMPORTANT
NSO Science Olympiad Workbook Grade 7>Chapter 3 - Heat>EXERCISES>Q 17
Which of the following quantities increases when a liquid at room temperature becomes a gas at its boiling point?
EASY
7th Foundation
IMPORTANT
NSO Science Olympiad Workbook Grade 7>Chapter 3 - Heat>EXERCISES>Q 18
You put a metal key into its metal lock and find that the key is too tight. Which of the following methods will you adopt to make the key fit properly?