Question

An object is placed at a distance
of 12cm in front of concave mirror.
It forms a real image four times
larger than the object, Calculate
The distance of the image from
mirror.
​

Answer 1

Answer :-

→ v = - 48 cm .

Step-by-step explanation :-

We have,

→ Object distance = 12 cm .

$\therefore$ u = - 12 cm .[ Since, object is placed in front of mirror ] .

And,

→ It forms a real image four times larger than the object .

$\therefore$ m = - 4 . [ Since, it forms a real image. So, magnification will be in minus ] .

To find :-

→ The distance of the image from mirror ( v ) .

Now,

We know that :-

$\tt \because m = \frac{ - v}{u} . \\ \\ \sf \implies - 4 = \frac{ - v}{ - 12} . \\ \\ \sf \implies v = - 4 \times 12. \\ \\ \huge \pink{ \boxed{ \boxed{ \it \therefore v = - 48 \: cm.}}}$

Hence, it is solved .

Answer 2

u = - 12 cm .[ Since, object is placed in front of mirror ] .

m = - 4 . [ Since, it forms a real image. So, magnification will be in minus ] .

Then, m = -v/u .

=) -4 = -v / -12 .

=) v = -4 × 12 .

.°. v = -48 cm .