Two plane mirrors kept at 60° form 5 images of an object kept between them.
The number of images formed by two plane mirrors kept at a particular angle are as follows:
n = [(360°/Θ) - 1 ] when (360°/Θ) is even integer, and
n = (360°/Θ) when (360°/Θ) is odd integer
Here, Θ is the angle between the two mirrors.
Therefore, the number of images formed (n) = [(360°/60°) - 1 ] = [6 - 1] = 5