a plane mirror is placed with its plane at an angle 30 degrees. plane of mirror is perpendicular to the xy plane and the length of the mirror is 3 m. an insect moves along x-axis starting from a distant point,with speed 2 cm/s. the duration of the time for which the insect can see its own image in the mirror is

Let the position of object be at distance A from origin... Then By ray diagram it can be shown that when insect is to left of A all its reflected will be towards right of A so it cannot see its image bcoz rays are not reaching it..When the insect is right of A its reflected rays will be on both sides of ut that means the insect will be in the field of view of uts inage so it can see its image …

So it can see its image upto origin 

2×t = 3/cos60°× 100 

t= 300 sec.

As diagram is provided in question so it will be easy to understand..

Thanks!! Keep me in your blessing...