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A 2.0 m tall object is 12.0 m from a convex lens that has a 4.0

m focal length. Determine the image size and distance from the
lens.?

User XMort
by
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1 Answer

1 vote
Great question! To determine the image size and distance from the lens, we can use the lens formula:

1/f = 1/v - 1/u

where f is the focal length of the lens, v is the image distance, and u is the object distance.

Given that the focal length (f) is 4.0 m and the object distance (u) is 12.0 m, we can substitute these values into the formula:

1/4 = 1/v - 1/12

To solve for v, we need to rearrange the equation:

1/v = 1/4 + 1/12

1/v = (3 + 1)/12

1/v = 4/12

1/v = 1/3

Now, we can find the value of v by taking the reciprocal of both sides:

v = 3 meters

So, the image distance (v) is 3 meters.

To find the image size, we can use the magnification formula:

magnification (m) = -v/u

Given that the object height (h) is 2.0 meters, we can substitute these values into the formula:

m = -v/u = -3/12 = -1/4

The negative sign indicates that the image is inverted. The magnification value of -1/4 means that the image is one-fourth the size of the object.

Therefore, the image size is 1/4 of the object's height, which is 1/4 * 2.0 = 0.5 meters.

So, the image size is 0.5 meters and the image distance is 3 meters from the convex lens.

I hope this explanation helps! Let me know if you have any further questions.
User Chriss Paul
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