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Class 10 - Mathematics - CHAPTER 12: Surface Areas & Volumes - Exercise 12.1Question 4
Class 10 - Mathematics - CHAPTER 12: Surface Areas & Volumes - Exercise 12.1
Question. 4
The shape of a glass (tumbler) (see Fig.) is usually in the form of
(A)
a cone
(B)
frustum of a cone
(C)
a cylinder
(D)
a sphere
Detailed Answer with Explanation:
Step 1: Look carefully at the glass (tumbler). It is wide at the top and becomes narrow as we go down.
Step 2: A cone also has this property — wide at one end and pointed at the other. But in a glass, the bottom is flat, not pointed.
Step 3: If we cut off the sharp tip of a cone and make the bottom flat, the shape we get is called a frustum of a cone.
Step 4: A cylinder has the same width from top to bottom, so it cannot be the shape of a glass.
Step 5: A sphere is completely round like a ball, which also does not match the shape of a tumbler.
Conclusion: Therefore, the glass (tumbler) is in the shape of a frustum of a cone.