X-rays → <span>They are commonly used in hospitals to produce photographs of bones which can be checked for breaks or fractures.</span> →<span> they can penetrate less </span>dense<span> matter such as skin and body tissue (but not bone)
ir rays </span>→help in maintaining the warmth of the earth →these are used in TV remote controls
A convex lens acts a lot like a concave mirror. Both converge parallel rays to a focal point, have positive focal lengths, and form images with similar characteristics. A concave lens acts a lot like a convex mirror.