Question

Two plane mirrors are placed making an angle 60 in between them. For an object placed in between the mirrors,
the number of images formed will be:

Answer 1

$\Large\underline{\underline{\red{\sf \purple{\maltese}\:\: Given :- }}}$

$\implies\textsf{ Two plain mirrors are inclined at an angle of \sf 60^{\circ} }.\\\implies\textsf{ Object is placed between the mirrors .}$

$\Large\underline{\underline{\red{\sf \purple{\maltese}\:\: To \ Find :- }}}$

$\implies\textsf{ The number of images formed .}$

$\Large\underline{\underline{\red{\sf \purple{\maltese}\:\: Answer :- }}}$

The number of images formed by two mirrors when object is placed between them inclined at an angle $\theta$ is $\sf \dfrac{ 360}{\theta}-1$ if $\sf\dfrac{360}{\theta}$ is even . Hence here ,

$\sf:\implies\pink{ n_{image} = \dfrac{ 360}{\theta}-1} \\\\\sf:\implies n_{image} = \dfrac{360}{60}-1 \\\\\sf:\implies n_{image}= 6 - 1 \\\\\sf:\implies\boxed{\pink{\mathfrak{ number_{images} = 5 }}}$

$\underline{\blue{\sf \therefore Hence \ the \ number\ of \ images \ is \ \textsf{\textbf{5 }}. }}$

$\rule{200}2$

$\Large\underline{\underline{\red{\sf \purple{\maltese}\:\: Some \ more \ Information :- }}}$

• If in case $\sf\dfrac{360}{\theta}$ is odd , then

(i) If the object is located symmetrically between two mirrors , then the number of images formed will be ,

$\qquad\boxed{\red{\bf n_{(images)}=\dfrac{360}{\theta} -1 }}$

(ii) If the object lies asymmetrically between the two mirrors then the number of images formed will be ,

$\qquad\boxed{\red{ \bf n_{(images)}=\dfrac{360}{\theta} }}$

• If $\sf\dfrac{360}{\theta}$ is fraction then the number of images formed will be equal to the integral part of the fraction .

• When two mirrors are kept parallel to each other , then the number of images formed will be infinite ( ∞ ) .