Our Science Room: 2020

Energy in Day-to-Day Life - part i

Energy is defined as the ability to do a work or produce a change.

We understand that energy is needed to do activities in our day-to-day life.

Sources of energy

Examples

Sun
Wind
Bio mass
Fossil Fuel
Flowing water
Geo thermal power
Nuclear power

Primary Source energy

Any source of energy that is captured and used directly from nature

Examples

Sun is the main primary energy source

Secondary source energy

Any source of energy that is obtained from a primary source through a transformation.

Examples

Electricity ➠➡➡ transformed from flowing water

Gasoline (Petrel, diesel, kerosene) ➡➡➡ (refined from crude oil)

Utilizing of energy to do work

Please refer the text book and try to do the following activities at home.

Materials required for them can be found easily at home.

Make a wind propeller.
Solar thermal box stove
Kudu Lipa
Activity 4.4: using wind energy to lift a weight

Further knowledge..

Let’s learn the following clip to understand how crude oil is extracted from the ground.

Kudulipa

Cond..

Sanjaya Sir..

Chapter-03

WATER AS A NATURAL RESOURCE

Water exists as three physical states as solid, liquid and gas.
Precipitation, surface water and ground water are the three ways that water exists.
Further, according to the salinity water can be divided in to three types as fresh water, brackish water and marine water.
Although water covers 70% of the earth surface, the consumable amount of water is 0.01%.

Assignment 01.

Section A

1.What are three states of water? Mention two examples for each.

02.Write down the experimental steps to find the states of water.

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04.What are the three categories of water found in the environment? Give two examples
for each.
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05.Based on the salinity, water can be divided in to three types. Mention each with 2
examples

Section B

01.Fill in the blanks with correct ward

When liquid water is heated, it can be converted in to…………………...............
Snow is an example for the………………………………state of water.
Sleet that is fallen to the earth is one of the type of……………………………...
Water in ponds is one of the type of………………………………………………
Almost two point five percent of the water on the earth surface is…………water.
Brackish water can be found in……………………............
Agro chemicals……………………………..pure water.
By cooling vapor……………………..…..can be obtained
Water is an important factor to plants for…………………………………
Marine water accounts for………………….of the total water on the earth.

02.You are given three test tubes A,B, & C so as the final volume up to 50 ml.Salt in
B & C are dissolved well.

A-50 ml of water
B-3 grams of salt + water
C-7 grams of salt + water

A B C

i.Arrange the test tubes in ascending order by considering the masses
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ii.Which test tube can be assumed as marine water? Explain your answer
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iii.What is the test tube that can be assumed as brackish water? Explain your answer
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iv.What is the conclusion that can be taken from the above activity?
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03.Describe an experiment to show that the atmosphere consists of water vapors with a
diagram.
Write two instances in our day to day life.
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Sanjaya Sir..