Answered

Roshan makes the table below to describe how to draw a ray diagram for a convex lens.

| Ray from Object to Lens | After Passing Through Lens |
|---------------------------------------------------------|------------------------------------------------------------------------------|
| Draw through the focal point on the same side of the lens as the object. | The ray goes parallel to the main axis. |
| Draw parallel with the main axis. | The ray goes away from the main axis as though it came from the focal point near the object. |
| Draw to the center of the lens. | The ray goes straight through and does not bend. |

What error did Roshan make?

A. The ray that goes through the center should bend and go through the focal point on the other side.
B. The ray that starts out parallel with the main axis should bend toward the axis and go through the focal point on the other side.
C. The ray that goes parallel to the main axis after passing through the lens should also be parallel from the object to the lens.
D. The rays in the table describe how rays are drawn for a concave lens rather than for a convex lens.



Answer :

GinnyAnswer
Let's carefully examine the table and the described behavior of the rays in relation to a convex lens.

### Examination of Roshan's Descriptions:

1. First Ray:
- Description: "Draw through the focal point on the same side of the lens as the object."
- Expected for Convex Lens: A ray that passes through the focal point on the object side should emerge parallel to the main axis after passing through the lens.
- This Description: "The ray goes parallel to the main axis."
- Verification: This is correctly described for a convex lens.

2. Second Ray:
- Description: "Draw parallel with the main axis."
- Expected for Convex Lens: A ray parallel to the main axis should pass through the focal point on the opposite side of the lens after emerging.
- This Description: "The ray goes away from the main axis as though it came from the focal point near the object."
- Verification: This description is erroneous for a convex lens. This describes the behavior of a concave lens, where parallel rays diverge after passing through the lens as if they are coming from the focal point on the same side as the object.

3. Third Ray:
- Description: "Draw to the center of the lens."
- Expected for Convex Lens: A ray passing through the center of the lens should continue straight without bending.
- This Description: "The ray goes straight through and does not bend."
- Verification: This is correctly described for a convex lens.

### Analysis:

Only one statement (the second description) within Roshan's table is incorrect when describing the behavior of rays with a convex lens. The second ray's description matches the behavior of a concave lens rather than a convex lens. Hence, the error in the table is that this second ray's behavior describes a situation applicable to a concave lens.

### Conclusion:

The error Roshan made is that the rays in the table describe how rays are drawn for a concave lens rather than for a convex lens. This means Roshan's explanation for the second ray, "The ray goes away from the main axis as though it came from the focal point near the object," is mistaken for a convex lens and correctly describes a concave lens.

Therefore, the correct error description is:

"The rays in the table describe how rays are drawn for a concave lens rather than for a convex lens."

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