CBSE Class 4 Maths Shapes Spaces And Patterns Worksheet

CHAPTER : 7 SHAPES, SPACE AND PATTERNS

Fill in the blanks:-

Question 1. __________ shapes are called closed curves.
Answer: Simple
In simple words: A shape that starts and ends at the same point without crossing itself is a simple closed curve.

Exam Tip: Remember that a closed curve does not have any open ends.

Question 2. Closed shapes formed by straight lines are called __________
Answer: Polygons
In simple words: Any 2D shape made completely of straight line segments is called a polygon.

Exam Tip: Circles and curves are not polygons because they are not made of straight lines.

Question 3. A __________ is named according to the number of sides it has.
Answer: Polygon
In simple words: Polygons get their specific names (like triangle, quadrilateral, pentagon) based on how many sides they possess.

Question 4. A polygon with three line segments is called a __________
Answer: Triangle
In simple words: A three-sided polygon is a triangle.

Exam Tip: 'Tri' means three.

Question 5. A polygon with 4 line segments is called a __________
Answer: Quadrilateral
In simple words: A four-sided polygon is a quadrilateral.

Exam Tip: 'Quad' means four.

Question 6. A __________ is a quadrilateral with opposite sides equal.
Answer: Rectangle (or Parallelogram)
In simple words: A rectangle has four sides where the opposite sides are equal in length.

Exam Tip: A rectangle also has four right angles.

Question 7. A __________ is a quadrilateral with all sides equal.
Answer: Square (or Rhombus)
In simple words: A square is a special quadrilateral where all four sides are of equal length.

Question 8. A __________ is a simple closed curve.
Answer: Circle (or Oval)
In simple words: A circle is a round shape forming a simple closed curve.

Exam Tip: Any shape drawn without lifting your pencil that ends where it started and has no corners can be an example.

Question 9. The length of the circle is called its __________
Answer: Circumference
In simple words: The distance around the boundary of a circle is its circumference.

Exam Tip: Think of circumference as the perimeter of a circle.

Question 10. The point where the diameter and the radius meet is called __________ of the circle.
Answer: Centre
In simple words: The exact middle point of the circle is the centre, from which radii start and diameters pass through.

Exam Tip: The centre is always equidistant from any point on the boundary of the circle.

Question 11. In the given figure
a) Centre of the circle is __________
b) Radius of the circle is __________
c) Diameter of the circle is __________
Answer:
a) O
b) OP (or OM, ON)
c) MN
In simple words: Point O is in the middle, line segment OP goes from centre to edge, and line segment MN goes right across passing through the centre.

Exam Tip: Radius connects the centre to the boundary; diameter connects two points on the boundary through the centre.

Question 12. The __________ is twice the length of the radius.
Answer: Diameter
In simple words: Diameter = 2 \times \text{Radius}

Exam Tip: Always remember \(\text{Diameter} = 2 \times r\).

Question 13. The __________ is half the length of the diameter.
Answer: Radius
In simple words: Radius = \text{Diameter} \div 2

Exam Tip: Always remember \(\text{Radius} = \frac{\text{Diameter}}{2}\).

Question 14. The radius of a circle is \(3\text{cm}\). Its diameter is __________
Answer: \(6\text{cm}\)
Diameter = \(2 \times \text{Radius} = 2 \times 3\text{cm} = 6\text{cm}\)
In simple words: Multiply the radius by 2 to get the diameter.

Exam Tip: Show the multiplication step clearly.

Question 15. The diameter of a circle is \(16\text{m}\). Its radius is __________
Answer: \(8\text{m}\)
Radius = \(\text{Diameter} \div 2 = 16\text{m} \div 2 = 8\text{m}\)
In simple words: Divide the diameter by 2 to get the radius.

Exam Tip: Show the division step clearly.

Do the following

Question 1. Name the parts of the circle.
a) Centre __________
b) Diameter __________
c) Radius __________
d) AB __________
e) CD __________
Answer:
a) Centre: e
b) Diameter: CD
c) Radius: eA (or eB, eD)
d) AB: Chord (or arc/line segment)
e) CD: Diameter
In simple words: Identify each labelled point or line segment from the given diagram.

Exam Tip: Check whether the line passes through the centre to distinguish between a chord and a diameter.

Question 2. Give the radius of the circle with the following diameter:
a) \(32\text{cm}\)
b) \(10\text{m}\)
c) \(74\text{m}\)
d) \(90\text{cm}\)
e) \(16\text{cm}\)
f) \(52\text{m}\)
g) \(28\text{cm}\)
h) \(50\text{m}\)
Answer:
To find the radius, divide each diameter by 2:
a) \(32\text{cm} \div 2 = 16\text{cm}\)
b) \(10\text{m} \div 2 = 5\text{m}\)
c) \(74\text{m} \div 2 = 37\text{m}\)
d) \(90\text{cm} \div 2 = 45\text{cm}\)
e) \(16\text{cm} \div 2 = 8\text{cm}\)
f) \(52\text{m} \div 2 = 26\text{m}\)
g) \(28\text{cm} \div 2 = 14\text{cm}\)
h) \(50\text{m} \div 2 = 25\text{m}\)
In simple words: Radius is always half of the diameter.

Exam Tip: Always include the correct unit of measurement (\(\text{cm}\) or \(\text{m}\)) in your final answer.

Question 3. Give the diameter of circle with the following radius.
a) \(30\text{cm}\)
b) \(25\text{m}\)
c) \(85\text{cm}\)
d) \(9\text{m}\)
e) \(50\text{cm}\)
f) \(18\text{m}\)
g) \(72\text{m}\)
h) \(44\text{cm}\)
Answer:
To find the diameter, multiply each radius by 2:
a) \(30\text{cm} \times 2 = 60\text{cm}\)
b) \(25\text{m} \times 2 = 50\text{m}\)
c) \(85\text{cm} \times 2 = 170\text{cm}\)
d) \(9\text{m} \times 2 = 18\text{m}\)
e) \(50\text{cm} \times 2 = 100\text{cm}\)
f) \(18\text{m} \times 2 = 36\text{m}\)
g) \(72\text{m} \times 2 = 144\text{m}\)
h) \(44\text{cm} \times 2 = 88\text{cm}\)
In simple words: Diameter is always double the radius.

Exam Tip: Double check your multiplication for larger numbers like 85 and 72.

Question 4. Say whether the following are true or false.
a) All the radii of a particular circle are of equal length.
b) The diameter is half the radius.
c) The diameter goes through the centre of the circle.
Answer:
a) True
b) False
c) True
In simple words: Radii from centre to any point on a circle are always equal. Diameter is twice the radius, not half, and it always passes through the centre.

Exam Tip: Read every statement carefully to avoid mixing up radius and diameter properties.