Chronology Current Month Current Thread Current Date
[Year List] [Month List (current year)] [Date Index] [Thread Index] [Thread Prev] [Thread Next] [Date Prev] [Date Next]

Beats: quiz question



Today I put this question on a Waves test.

4. In color theory red light (4.8 x 1014 HZ) and green light (5.7 x 1014
Hz) combine to yield yellow. A student proposed that this is an example of
the beats phenomenon.
a. What would be the beat frequency of these colors? Would this be an
observable frequency?
b. Is the student justified in his hypothesis?

This was one of those thoughts I had without time to check whether this
harebrained idea has any basis in fact or not. The average of these two
frequencies is in the yellow. The difference is IR, I think. I just wanted
to do something that was not sound. One student said that beats only
happens with sound. I know better than that.

As always looking for wisdom.

Ken Fox
Science Department Coordinator
IB Physics Teacher
Smoky Hill High School
Aurora, CO
kfox@mail.ccsd.k12.co.us