Answer:
There are three reasons
Step-by-step explanation:
1. When the screen is placed far away from the ball than he/she cannot get shadow on the screen.
2. The beam of light from the torch is falling parallel to the screen on the ball due to which the ball is not able to obstruct the whole light from the torch and shadow is not obtained.
3. The torch is kept away from the ball. This makes the source of light far away hence the sufficient light is not reached to the ball.