Answer –
According to the question –
Angle of deflection is θ = 3.5°
The distance of the screen from the mirror is D = 1.5 m
The deflection undergone by the reflected rays are twice the angle of deflection, so –
2θ = 7.0°
The displacement (d) of the reflected spot of light is determined in the following manner –
$\tan 2\Theta =\frac{d}{1.5}$
Therefore, we have –
d = 1.5 x tan7o = 0.184 m
d = 18.4 cm
Hence, 18.4 cm is the displacement of the refracted spot of light.