Question

An object 5 cm tall is placed 1 m from a concave spherical mirror which has a radius of curvature
of 20 cm. The size of the image is
(1) 0.11 cm
(2) 0.50 cm
(3) 0.55 cm
(4) 0.60 cm

​

Answer 1

the answer of your question is 0.55 CM

Answer 2

Answer:

R = 20cm

F = 10cm

u = 100cm

therefore the image formed is real and inverted.

As the object is in the left side of the mirror, the u will be = -100cm

f = -10cm

therefore let v = -x

therefore, (-1/100) + (-1/x) = -1/10

=> -(100+x)/100x = -1/10

=>(100+x) = 100x/10

=> 100+x = 10x

=> 9x = 100

=> x = 11.11 cm

therefore v = -x = -11.11cm

now we have H1 = height of object = 5cm

u = -100cm

v = -11.11cm

so let H2 be = height of image = -x (as it's inverted)

so -x/5 = -(-11.11/-100)

=> -x/5 = -11.11/100

=> -100x/5 = -11.11

=> -20x = -11.11

=> x = 11.11/20

=> x = 0.56cm (approx)

therefore, H2 = -x = -0.56cm = (option 3)

Hope it helped :)