Question

A plane mirror of length $8$ cm is moving with speed $3$ m/s towards a wall in the situation as shown in the figure. Size of spot formed on the wall is $32/x$ cm. Find the value of $x$.

Answer 1

so size of the spot

$A^{\prime }{B}^{\prime }=4+12=16cm$

$\frac{32}{x}=16$

$x=2cm$