Question

what is virtual image

Answer 1

in simple words the image which cannot be obtained on screen is known as virtual image
virtual image is a fact that really don't exist but seems like it exits.
virtual image is that image which is formed when the light rays coming from an object do not actually meet, but appear to meet when produced backwards of mirror.

Answer 2

In optics, a virtual image is an image formed when the outgoing rays from a point on an object always diverge. The image appears to be located at the point of apparent divergence. Because the rays never really converge, a virtual image cannot be projected onto a screen.