Question

What will be the shape of the shadows formed on screens A and B when both the torches are switched on?

• A. Screen A: Rectangular
  Screen B: Rectangular
• B. Screen A: Rectangular
  Screen B: Circular
• C. Screen A: Circular
  Screen B: Circular
• D. Screen A: Circular
  Screen B: Rectangular

Answer 1

The correct option is B Screen A: Rectangular

Screen B: Circular

The correct answer is Option C-Screen A: rectangular, ​Screen B: Circular.
Light travels in a straight line. A shadow is an area where light is absent. so, if the light falls on an opaque object like a water bottle. The shadow will be obtained on the screen. As the direction of the light source changes the shape of the shadow will change. Therefore the shape of the shadow formed on screen A and B will not be the same.
In the first case(screen A), the rectangular cross-section is blocking the light. So the shape of the shadow will be rectangular. In the second case the circular cross-section is blocked by the light. So the shape of the shadow is circular. Hence option C is correct.