Page 93 - Science class 4

High Order Thinking Skill (HOTS)

1. You are doing your homework and your brother is playing the cricket.
Which action needs more energy?

2. You can tear paper with your hands as well as using scissors. Which way is

advised and why?

Learn ‘N’ Fun

Complete the following diagram :

VARIOUS TYPES OF MACHINES VARIOUS TYPES OF MACHINES ARIOUS TYPES OF MACHINES
V

ScrewcrewScrew
W Wheel
L L
Liveriveriver Wheelheel S
and axlend axlend axle
a a
Testing Zone

To show that a screw is an inclined plane wrapped around a cylinder.

Materials required : paper, pencil, sketch pen and scissors.

Method : a. Cut a square paper in two pieces diagonally.

b. Draw a line along the longest side of one of the

triangles with the sketch pen.

c. Now, place the triangle such that the shortest

side is closest to the side of the pencil.

d. Wrap the triangle around the pencil by rolling
the pencil.

e. You will see that you have made a screw.

Practical Approach

1. On a map of India, find out some important dams and the names of rivers they
are built across.
2. Find out which country is famous for windmills. Spot the country on a world

map.

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