The wave period is the amount of time it takes a wave to
pass a point. Wave frequency is what you
call the number of waves that pass in a certain point per second. If you
increase the wave length of any wave, you decrease the wave frequency (the
number of waves that pass in a certain point per second).
Answer:
The tiny muscles that make up the iris, known as the circular and radial muscles, relax and contract to maintain a fairly constant level of light entering the eye. In bright light, the circular muscles contract whilst the radial muscles relax. This causes the pupil to constrict and less light enters the eye.
Explanation: