NCERT Solutions Class 7 Math Chapter 13 Visualising Solid Shapes Exercise 13.4

NCERT Solutions Class 7 Math Chapter 13 Visualising Solid Shapes

TextbookNCERT
Class 7th
Subject Mathematics
Chapter13th
Chapter NameVisualising Solid Shapes
CategoryClass 7th Mathematics
Medium English
SourceLast Doubt

NCERT Solutions Class 7 Math Chapter 13 Visualising Solid Shapes

Chapter – 13

Visualising Solid Shapes

Exercise 13.4

Question 1. A bulb is kept burning just right above the following solids. Name the shape of the shadows obtained in each case. Attempt to give a rough sketch of the shadow. (You may try to experiment first and then answer these questions).

Solution: When the light falls just above the solids.
(i) A ball; the shadow looks like a circle.
(ii) A cylindrical pipe; the shadow looks like nearly rectangular.
(iii) A book; the shadow looks like nearly rectangular.
Question 2. Here are the shadows of some 3-D objects, when seen under the lamp of an overhead projector. Identify the solid(s) that match each shadow. (There may be multiple answers for these!)

Solution: 
(i) The given shadow corresponds to a sphere.
(ii) The given shadow corresponds to a cube.
(iii) The given shadow corresponds to a pyramid.
(iv) The given shadow corresponds to a cuboid or a cylinder.
Question 3. Examine if the following are true statements:
(i) The cube can cast a shadow in the shape of a rectangle.
(ii) The cube can cast a shadow in the shape of a hexagon.

Solution: 
(i) The given statement is true.
(ii) The given statement is false.