Physics, asked by yashkundu4212, 1 year ago

a convex mirror has focal length 20cm an object placed in front of it at a distance of 10cm its image is formed tell how (in complete sense)

Answers

Answered by lakshaya98
0

Answer:

For convex lens,

Focal length, f=+20 cm

Object distance, u=−40 cm

Using lens formula, we have

f

1

=

v

1

u

1

20

1

=

v

1

−40

1

v

1

=

20

1

40

1

=

40

2−1

=

40

1

⇒v=+40 cm

Now, for convex mirror, we have

Focal length, f=

2

R

=

2

20

=+10 cm

Object distance, u=+(40−15) cm=+25 cm

Using mirror formula, we have

f

1

=

v

1

+

u

1

10

1

=

v

1

+

25

1

v

1

=

10

1

25

1

=

50

5−2

=

50

3

⇒v=+

3

50

cm

∴ The final image is formed at a distance of

3

50

cm from the convex mirror or at a distance of (

3

50

+15)cm=

3

95

cm from the convex lens.

The final image is a virtual image.

Answered by nirman95
2

Given:

A convex mirror has focal length 20cm an object placed in front of it at a distance of 10cm.

To find:

Image formation and it's characteristics?

Calculation:

First of all, let's find the image distance:

Applying MIRROR FORMULA:

 \sf \therefore \:  \dfrac{1}{f}  =  \dfrac{1}{v}  +  \dfrac{1}{u}

 \sf \implies \:  \dfrac{1}{20}  =  \dfrac{1}{v}  +  \dfrac{1}{( - 10)}

 \sf \implies \:  \dfrac{1}{20}  =  \dfrac{1}{v}   -   \dfrac{1}{ 10}

 \sf \implies \: \dfrac{1}{v}    =    \dfrac{1}{ 10}  +  \dfrac{1}{20}

 \sf \implies \: \dfrac{1}{v}    =    \dfrac{2 + 1}{ 20}

 \sf \implies \: \dfrac{1}{v}    =    \dfrac{3}{ 20}

 \sf \implies \:v    =    \dfrac{20}{ 3}

 \sf \implies \:v    =   6.67 \: cm

Since , image distance is positive, we can say that a virtual image is produced by the convex mirror.

Now , any convex mirror produces image with same characteristics as follows:

  • Image will be virtual.

  • Image will be diminished.

  • Image will be erect.

Hope It Helps.

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