Maharashtra Board Class 5 Maths Chapter 13 Three Dimensional Objects and Nets Set 51 Solutions

Question 1. The first column shows a structure made of blocks. The other columns show different views of the structure in two dimensions. Say whether each view is from the front, from a side or from above.
ℹ️ चित्र व्याख्या (Diagram Explanation): इस चित्र में तीन पंक्तियों में ब्लॉक से बनी संरचनाएं दिखाई गई हैं। पहली पंक्ति में एक आयताकार ब्लॉक समूह, दूसरी में 'L' आकार की संरचना और तीसरी में सीढ़ीनुमा ब्लॉक समूह है। इन संरचनाओं के विभिन्न द्वि-आयामी दृश्य दिखाए गए हैं और छात्रों को पहचानना है कि प्रत्येक दृश्य सामने, बगल या ऊपर से है।
Answer:

In simple words: The exercise asks to identify the perspective (front, side, or top) of different 2D views for given 3D block structures. By visually comparing the 2D representations with the 3D object, one can determine the correct viewpoint.

🎯 Exam Tip: Pay close attention to the number of blocks visible in each dimension and their arrangement to correctly identify the view. Practice with various block structures for better understanding.

Question 2. Draw three pictures of each of these three-dimensional objects - a table, a chair and a water bottle as viewed from the front, from a side and from above.
Answer:

In simple words: This question asks students to visualize common 3D objects like a table, chair, and water bottle from different perspectives: front, side, and top, and represent these 2D views. This helps in understanding how 3D objects appear when viewed from various angles.

🎯 Exam Tip: When drawing views, ensure all visible edges and surfaces from that particular perspective are accurately represented. Practice with simple objects first to master this skill.

Nets

Last year we saw that cutting some edges of a box and laying it out flat gives us the net from which it was made.
The two dimensional shape from which a three dimensional object can be made by folding is called the 'net' of that object.

1. By folding the cardboard shown below, along the lines shown in it, we get a three dimensional object (box). In this shape, all surfaces are square.
ℹ️ चित्र व्याख्या (Diagram Explanation): यह एक क्यूब का नेट दिखाता है, जिसमें छह वर्ग फलक एक-दूसरे से जुड़े हुए हैं, जिन्हें मोड़कर एक घन बनाया जा सकता है। इसके बगल में एक पूर्ण 3D घन का चित्रण है, जो दर्शाता है कि नेट को मोड़ने के बाद वस्तु कैसी दिखेगी।

An object of this shape is called a cube.

2. The net of another cardboard box is shown in the figure below. By folding along the lines in this net and joining the edges to each other, we can see that a three dimensional box is formed. The surfaces of this box are rectangular in shape.
ℹ️ चित्र व्याख्या (Diagram Explanation): यह एक घनाभ का नेट दिखाता है, जिसमें आयताकार फलक एक-दूसरे से जुड़े हुए हैं, जिन्हें मोड़कर एक घनाभ बनाया जा सकता है। इसके बगल में एक पूर्ण 3D घनाभ का चित्रण है, जो दर्शाता है कि नेट को मोड़ने के बाद वस्तु कैसी दिखेगी।

An object of this shape is called a cuboid.

Activity :

Draw the nets shown below on card sheet. Cut out the shapes and find out the shapes of the boxes they form.
(1)
ℹ️ चित्र व्याख्या (Diagram Explanation): यह एक नेट है जिसमें छह वर्ग फलक 'T' आकार में व्यवस्थित हैं, जिन्हें मोड़कर एक घन बनाया जा सकता है।
(2)
ℹ️ चित्र व्याख्या (Diagram Explanation): यह एक और नेट है जिसमें आयताकार और वर्गाकार फलक इस तरह से जुड़े हैं कि उन्हें मोड़कर एक घनाभ बनाया जा सकता है।

A five-square net (Pentomino)
In the figure alongside, five squares of the same size are placed together with their sides joined.
ℹ️ चित्र व्याख्या (Diagram Explanation): यह एक पेंटोमिनो दिखाता है, जो पांच समान आकार के वर्गों को एक साथ उनके किनारों से जोड़कर बनाया गया एक विन्यास है।

Such an arrangement of five squares is called a 'five-square net' or a 'pentomino'.

By folding along the edges of such a five-square net, an open box is formed.
ℹ️ चित्र व्याख्या (Diagram Explanation): यह एक खुले बक्से (एक घन जिसकी एक फलक गायब है) का 3D चित्रण है, जिसे एक पेंटोमिनो नेट को मोड़कर बनाया जा सकता है।

Activity :

Some five-square nets are given below. Draw these nets on a card sheet. Make open boxes from these nets.
ℹ️ चित्र व्याख्या (Diagram Explanation): इस खंड में तीन अलग-अलग पेंटोमिनो नेट दिखाए गए हैं, जिनमें से प्रत्येक पांच वर्गों से बना है। इन नेट को कार्ड शीट पर बनाने और उन्हें मोड़कर खुले बक्से बनाने का निर्देश दिया गया है।

Try to find out other five-square nets that can be used to make open boxes.

A riddle

Question. The net of a cube-shaped dice is given alongside. If a dice is made of this net, which of the following shapes will it definitely not resemble?
ℹ️ चित्र व्याख्या (Diagram Explanation): इस प्रश्न में एक पासे (dice) का नेट दिखाया गया है, जिस पर संख्यात्मक मानों (बिंदुओं) को दर्शाया गया है। इसके नीचे पांच अलग-अलग पासे के दृश्य दिए गए हैं, जिन पर भी बिंदु दर्शाए गए हैं। छात्रों को यह पहचानना है कि नेट को मोड़कर बनाए गए पासे से कौन सा दिया गया पासा मेल नहीं खाएगा।
(1)
(2)
(3)
(4)
(5)
Answer: (The specific option is not provided in the source content.) In simple words: This riddle asks students to mentally fold a given 2D net of a dice into a 3D cube and then determine which of the provided 3D dice configurations is impossible to achieve from that specific net, usually by checking opposite faces or adjacent faces.

🎯 Exam Tip: To solve dice net problems, remember that opposite faces in a standard dice net are usually separated by one face. Visualize the folding process and trace the numbers to see which faces will become adjacent or opposite.

Chapter 12 Perimeter And Area Problem Set 49 Additional Important Questions And Answers

Question 1. Draw the pictures of each of these three dimensional objects - Mobile, Oil tin as viewed from the front, from a side and from above.
Answer:

In simple words: This question requires students to draw or visualize how a mobile phone and an oil tin would appear when viewed from the front, from a side, and from directly above. It reinforces understanding of 2D projections of 3D objects.

🎯 Exam Tip: When sketching, focus on the primary outlines and key features visible from each specific viewpoint. Pay attention to the relative proportions and positions of elements.

Question 2. The three dimensional figure of block formation is shown in the figure along side. Draw as view from the front, from a side and from above (fig. drawn in answer part)
Answer:

In simple words: This question requires drawing the front, side, and top views for several given 3D block formations. It assesses a student's spatial reasoning and ability to project a 3D structure onto 2D planes.

🎯 Exam Tip: For complex block formations, count the number of blocks in each layer from the top view, and then project them onto the front and side views. Hidden blocks are important to consider for accurate representations.

Question 3. Draw the nets shown below on card sheet. Cut out the shapes and find out the shapes of the boxes they form.
Answer:

In simple words: This question involves visualizing 3D objects from their 2D nets. Students are asked to draw given nets, cut them out, and then fold them to understand which 3D shape (like a cube or cuboid) each net forms.

🎯 Exam Tip: When working with nets, carefully count the number of faces and observe their shapes (square, rectangle) to predict the resulting 3D object. Practice folding various nets to improve spatial reasoning.