Question

an object having size 2 cm, placed 10 cm in front of a concave mirror having focal length 8 cm. Calculate the position, nature and size of Image​

Answer 1

Answer:

Explanation:

Given that,

Focal length f=  

2

R

​  

 

Radius of curvature R=30

Object distance u=10cm

Height of object h  

o

​  

=2cm

From the mirror formula,

   

f

1

​  

=  

v

1

​  

+  

u

1

​  

 

−  

v

1

​  

=  

u

1

​  

−  

f

1

​  

 

−  

v

1

​  

=  

10

1

​  

−  

30

2

​  

 

−  

v

1

​  

=  

30

3−2

​  

 

v=−30cm

Now, the magnification is

 m=  

u

−v

​  

 

m=  

10

30

​  

 

m=3

Now, the height of image

 m=  

h  

o

​  

 

h  

i

​  

 

​  

 

3=  

2

h  

i

​  

 

​  

 

h  

i

​  

=6cm

Hence, the image distance is −30 cm, height of image is 6 cm and magnification is 3