The most important thing you should remember in order to get how is its linear momentum relative to the surface is that the<span> point on the circumference is moving at w rad/second.
Therefore, here is the solving formulae:
if </span>

you can easily get <span> linear momentum p :
</span>

I'm sure that helps.
A concave lens is a lens that has at least one of its surfaces or both surfaces curved inwards. Due to this reason, this lens diverges the light that falls on it and hence is also called a diverging lens. The concave lens is thinner in the middle compared to its edges. These are used in flashlights, binoculars, telescopes, etc.
Please see attached image for reference.