On a sunny day, does a bird or an aero plane flying high in the sky cast its shadow on the ground? Under what circumstances can we see their shadow on the ground?

Can you think of creating a shape that would give a circular shadow if held in one way and a rectangular shadow if held in another way?

A torch is placed at two different positions A and B, one by one, as shown in Fig. 11.9.

The shape of the shadow obtained in two positions is shown in Fig. 11.10.

Match the position of the torch and shape of the shadow of the ball.

Three identical towels of red, blue and green color are hanging on a clothes line in the sun. What would be the color of shadows of these towels?

In Fig. 11.11, a flower made of thick coloured paper has been pasted on the transparent glass sheet. What will be the shape and colour of shadow seen on the screen?

Suggest a situation where we obtain more than one shadow of an object at a time.

On a sunny day, does a bird or an aero plane flying high in the sky cast its shadow on the ground? Under what circumstances can we see their shadow on the ground?

Look at the figure given in Fig. 11.8.

Will there be any difference in the shadow formed on the screen in A and B.

Three torches A, B and C shown in Fig. 11.7 are switched on one by one. The light from which of the torches will not form a shadow of the ball on the screen.

A sheet of plywood, a piece of muslin cloth and that of a transparent glass, all of the same size and shape were placed at A one by one in the arrangement shown in Fig. 11.12. Will the shadow be formed in each case. If yes, how will the shadow on the screen be different in each case? Give reasons for your answer.

A football match is being played at night in a stadium with flood lights ON. You can see the shadow of a football kept at the ground but cannot see its shadow when it is kicked high in the air. Explain.