8. Flashcards
Which of the following is a correct characteristic of translucent objects?
a) They completely block the passage of light.
b) They allow light to pass through but scatter it.
c) They allow light to pass through without any distortion.
d) They do not cast any shadows.
Answer:
b) They allow light to pass through but scatter it.
Explanation:
Translucent objects partially allow light to pass through but scatter the light, preventing a clear view of objects on the other side.
Which property of light is primarily demonstrated in the working of a pinhole camera?
a) Light bends around corners.
b) Light travels in straight lines.
c) Light scatters in different directions.
d) Light gets absorbed by opaque surfaces.
Answer:
b) Light travels in straight lines.
Explanation:
The formation of an inverted image in a pinhole camera is due to the rectilinear propagation of light (light traveling in straight lines).
Which of the following phenomena cannot be explained using the principle of rectilinear propagation of light?
a) Formation of shadows
b) Working of pinhole cameras
c) Reflection from a plane mirror
d) Formation of an eclipse
Answer:
c) Reflection from a plane mirror
Explanation:
Rectilinear propagation explains the straight-line travel of light, which is crucial for shadow formation, pinhole camera operation, and eclipses.
Reflection involves the bouncing back of light at a surface and does not solely depend on straight-line propagation.
Consider the following statements regarding pinhole cameras:
1 They work based on the principle of rectilinear propagation of light.
2 The image formed is always inverted.
3 It can form images of all types of objects, regardless of brightness.
Which of the above statements is/are correct?
a) 1 and 2 only
b) 2 and 3 only
c) 1 and 3 only
d) 1, 2, and 3
Answer:
a) 1 and 2 only
Explanation:
Pinhole cameras rely on the fact that light travels in straight lines (rectilinear propagation).
The image formed is inverted due to the way light rays cross at the small aperture.
Bright objects are necessary for the image to be visible clearly.
In which of the following scenarios can a shadow not be formed?
When the light source is diffused, such as in foggy weather.
When the object is transparent.
When the distance between the light source and object is very large.
Options:
a) 1 only
b) 2 only
c) 1 and 2 only
d) 1, 2, and 3
Answer:
c) 1 and 2 only
Explanation:
A shadow cannot form with diffused light because light spreads in all directions, eliminating sharp edges.
Transparent objects do not block light and hence do not form shadows.
Which of the following is/are necessary conditions for the formation of a shadow?
1 The object must be opaque or translucent.
2 The light source must be larger than the object.
3 The object must block the path of light partially or fully.
a) 1 and 2 only
b) 1 and 3 only
c) 2 and 3 only
d) 1, 2, and 3
Answer:
b) 1 and 3 only
Explanation:
A shadow forms when an opaque or translucent object blocks the path of light. The size of the light source relative to the object does not necessarily impact the shadow’s formation but does affect its sharpness and clarity.
- What will happen if an object is placed directly between a light source and a translucent screen?
a) A sharp and clear shadow is formed on the screen.
b) A faint and blurred shadow is formed on the screen.
c) No shadow is formed at all.
d) The screen becomes opaque.
Answer:
b) A faint and blurred shadow is formed on the screen.
Explanation:
A translucent screen partially allows light to pass through, causing the shadow to appear faint and blurred.
Consider the following statements regarding transparent, translucent, and opaque objects:
1 Translucent objects do not form sharp shadows.
2 Opaque objects reflect all the light falling on them.
3 transparent objects can cast a faint shadow if their surface is uneven.
Which of the statements are correct?
a) 1 and 3 only
b) 2 only
c) 1 and 2 only
d) 1, 2, and 3
Answer:
a) 1 and 3 only
Explanation:
Translucent objects scatter light, so the shadow is blurry.
Opaque objects absorb and reflect light but do not reflect all light.
Transparent objects can cast faint shadows if their surfaces cause light diffusion.
Why does the image formed by a plane mirror appear laterally inverted?
a) Due to the straight-line propagation of light.
b) Because the left and right directions are swapped during reflection.
c) Because the mirror absorbs part of the light.
d) Due to scattering of light on the mirror surface.
Answer:
b) Because the left and right directions are swapped during reflection.
Explanation:
Lateral inversion occurs because the image appears as a reflection, flipping left and right while maintaining vertical orientation.
