Exercise 15.4 Page: 289
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).
(i)
(ii)
Solution:-
The shape of the shadow obtained from a cylindrical pipe is rectangle.
(iii)
Solution:-
The shape of the shadow obtained from a book is rectangle.
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!)
(i)
Solution:-
Cricket ball, water bottle cap, Disc
(ii)
Solution:-
Die, chalk box etc.
(iii)
Solution:-
Birthday cap etc.
(iv)
Solution:-
Book, keyboard, Mobile etc.
3. Examine if the following are true statements:
(i) The cube can cast a shadow in the shape of a rectangle.
Solution:-
The above statement is true.
(ii) The cube can cast a shadow in the shape of a hexagon.
Solution:-
The above statement is false.