class iv maths geometrical shapes & figures by k.lakshmi

Class IVClass IVMathsMaths

Geometrical Geometrical Shapes & Shapes &

FiguresFiguresBY K.LAKSHMIBY K.LAKSHMI

Geometrical ShapesGeometrical Shapes

• Geometrical shapes are two Geometrical shapes are two dimensional figures which can be dimensional figures which can be drawn on paper.drawn on paper.

• They can be divided intoThey can be divided into

1.1. Figures drawn with straight line Figures drawn with straight line segments known as Polygons.segments known as Polygons.

2.2. Figures drawn without line segments Figures drawn without line segments . .

PolygonsPolygons These can further be These can further be

classified depending classified depending on the number of line on the number of line segments present.segments present.

Classification of PolygonsClassification of Polygons

• A Polygon having A Polygon having 3 sides is called a 3 sides is called a Triangle.Triangle.

• A Polygon having A Polygon having 4 sides is called a 4 sides is called a quadrilateral. quadrilateral.

QuadrilateralsQuadrilaterals There are two special quadrilateralsThere are two special quadrilaterals

1.1. SquareSquare

2.2. RectangleRectangle

SquareSquare A square is a type of a quadrilateral that has all sides of A square is a type of a quadrilateral that has all sides of

equal length.equal length.

2 cm2 cm

2 cm2 cm2 cm2 cm

2 cm2 cm

RectangleRectangle A rectangle is a type of quadrilateral that has A rectangle is a type of quadrilateral that has

opposite sides equal.opposite sides equal.

6 cm6 cm

2 cm2 cm 2 cm2 cm

6 cm6 cm

Other PolygonsOther Polygons PENTAGON PENTAGON

is a 5 sided polygon is a 5 sided polygon HEXAGONHEXAGON

Is a 6 sided polygonIs a 6 sided polygon HEPTAGONHEPTAGON

Is a 7 sided polygonIs a 7 sided polygon

Figures without line Figures without line segmentssegments

All figures need not be drawn All figures need not be drawn with line segments only.with line segments only.

Some figures are drawn with Some figures are drawn with curves also.curves also.

CIRCLECIRCLE A circle has no sides. It is made of a A circle has no sides. It is made of a

curved line. curved line.

Geometrical Figures

These are 3 dimensional representations of geometrical shapes.

Eg cube, cylinder, sphere, cone

CUBECUBE A cube is a 3 A cube is a 3

dimensional view of dimensional view of a square or a a square or a rectangle.rectangle.

A cube has A cube has 1.1. 8 vertices8 vertices2.2. 12 edges12 edges3.3. 6 faces6 faces• Eg dice, boxEg dice, box

SPHERESPHERE A sphere is a 3 dimensional A sphere is a 3 dimensional

representation of a circle.representation of a circle. Eg a ball, earth, sun, moon.Eg a ball, earth, sun, moon.

CONECONE A Cone is a 3 A Cone is a 3

dimensional dimensional representation of a representation of a triangle and a triangle and a circle.circle.

Eg a joker’s cap, an Eg a joker’s cap, an icecream coneicecream cone

CYLINDERCYLINDER

A cylinder is a 3 dimensional representation of a A cylinder is a 3 dimensional representation of a rectangle (by folding it).rectangle (by folding it).

Eg chalk, pepsi can,a battery cell.Eg chalk, pepsi can,a battery cell.

PEPSI

Answer the following;1. What are Polygons?Ans) A SIMPLE CLOSED CURVE MADE OF LINE SEGMENTS

ALONE IS A POLYGON.2. How many sides does a circle have?Ans) A CIRCLE HAS NO SIDES.3. What is a 6 sided figure known as?Ans) HEXAGON.4. Name any 2 special types of quadrilaterals.Ans) SQUARE , RECTANGLE5. Fill in the blanks; A 3 sided Polygon is known as In a rectangle sides are equal.

Thanks to

Miss Sheetal Kale