Exercise 15.3
Question 1:
What cross-sections do you get when you give a:
(i) vertical cut (ii) horizontal cut to the following solids?
(a) A brick
(b) A round apple
(c) A die
(d) A circular pipe
(e) An ice-cream cone.
Answer 1:
S.No. | Name of article | Figure | Vertical cut | Horizontal cut |
(a) | A brick | |||
(b) | A round apple | |||
(c) | A die | |||
(d) | A circular pipe | |||
(e) | An ice-cream cone |
Exercise 15.4
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).
Answer 1:
S.No. | Object | Shadow | Shape's name |
(i) | A ball | Circle | |
(ii) | A cylindrical pipe | Line | |
(iii) | A book | Rectangle |
Question 2:
Here are the shadows of some 3-D objects, when seen under the lamp of the overhead projector. Identify the solid (s) that match each shadow.
(There may be multiple answers for these!)
Answer 2:
S. No. | Shadow | Shape's Name | 3-D objects |
(i) | Circle | Chapatti, Football, Disc, Plate etc. | |
(ii) | Square | Die, Square paper sheet, cubical magic box, Chalk box etc. | |
(iii) | Triangle | Ice-cream cone, Birthday cap, etc. | |
(iv) | Rectangle | Geometry box, Book, Table etc. |
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.
Answer 3:
(i) True
(ii) False
1. What are solid shapes? |
2. How do you visualize solid shapes? |
3. What is the importance of visualizing solid shapes? |
4. How can I improve my ability to visualize solid shapes? |
5. What are some real-life examples of solid shapes? |
|
Explore Courses for Class 7 exam
|