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a small cancle 10 cm tall is place 40 cm in front of a concave mirror whose radius of curvature is 16 cm

User Nelsonda
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1 Answer

3 votes

Answer:

The image is formed 40/3 cm behind the mirror, and its height is 3.33 cm.

Step-by-step explanation:

To find the image distance and height, we can use the mirror formula and magnification formula:

Mirror formula:

1/f = 1/d_o + 1/d_i

Magnification formula:

m = -d_i/d_o

Where f is the focal length, d_o is the object distance, d_i is the image distance, and m is the magnification.

Since the mirror is concave, the focal length is negative and given by:

f = -R/2

where R is the radius of curvature.

Substituting the values, we get:

f = -16/2 = -8 cm

d_o = -40 cm (since the object is in front of the mirror, the distance is negative)

Substituting these values into the mirror formula:

1/-8 = 1/-40 + 1/d_i

Simplifying:

-1/8 = -5/200 + 1/d_i

-1/8 = -1/40 + 1/d_i

-3/40 = 1/d_i

d_i = -40/3 cm

Since the image distance is negative, the image is formed behind the mirror.

Using the magnification formula:

m = -d_i/d_o

m = (-40/3)/(-40) = 1/3

Therefore, the image height is one-third the object height:

h_i = m * h_o

h_i = (1/3) * 10 cm = 3.33 cm

So, the image is formed 40/3 cm behind the mirror, and its height is 3.33 cm.

User McMa
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