Question 2 - Page 77 - Imagining Solids - Chapter 4 Class 8 - Exploring Some Geometric Themes (Ganita Prakash II

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Question 2 - Page 77 As we saw with the elephant, a given solid might have very different profiles from different viewpoints. Can you visualise solids that have the following contrasting profiles? We have these questions to answer A solid with a rectangular profile from one viewpoint and a circular profile from another viewpoint A solid with a circular profile from one viewpoint and a triangular one from another viewpoint A solid with a rectangular profile from one viewpoint and a triangular one from another viewpoint A solid with a trapezium shaped profile from one viewpoint and a circular one from another viewpoint A solid with a pentagonal profile from one viewpoint and a rectangular one from another viewpoint Question 8 (Rectangular + Circular) A cylinder. If you look at it from the side, it looks like a rectangle. If you look at it from the top, it's a circle. Question 9 (Circular + Triangular) A cone. If you look at the base, it's a circle. If you look at it from the side, it's a triangle. Question 10 (Rectangular + Triangular) A triangular prism (like a classic Toblerone chocolate box). Looking directly at the flat end gives a triangle, but looking at the long side gives a rectangle. Question 11 (Trapezium + Circular) A frustum (which is just a cone with the pointy top sliced off flat – like a bucket). Viewed from the top, you see concentric circles. Viewed from the side, you see a trapezium. Question 12 (Pentagonal + Rectangular) A pentagonal prism. Looking directly at the base gives a pentagon, while looking straight at one of its side faces gives a rectangle.