Sunlight contains many kinds of energy:
one is the visible light that we see, but it also
contains infrared radiation (heat), a range of
different kinds of ultraviolet (UV) radiation,
radio waves, X-rays, and more. This is all real
radiation, and it can burn you! The only
reason why we're not all fried is that the amounts
of the radiation are pretty small.
When you spend a long time in the sun, though,
your skin starts to burn just like it would if you
stood too close to a heat/infrared source or an
X-ray machine. Our skin doesn't really play a
role in that burning process--no more than a
piece of paper plays a role in the burning process
if you stick it in an oven.
Sunblocks don't change anything about our
skin, they just contain chemicals that absorb
different kinds of UV radiation. Since UV is
kind of radiation that burns us the fastest in
sunlight, sunblocks let us stay in sunlight
longer without getting burned.
Click Here to return to the search form.