This behavior helps Betty in <u>intellectual </u>development.
Explanation:
Formula which holds true for a leans with radii
and
and index refraction n is given as follows.
Since, the lens is immersed in liquid with index of refraction
. Therefore, focal length obeys the following.
and,
or,
= 32.4 cm
Using thin lens equation, we will find the focal length as follows.

Hence, image distance can be calculated as follows.


= 47.9 cm
Therefore, we can conclude that the focal length of the lens in water is 47.9 cm.
Downward movement under the force of gravity only.
wavelength = speed/frequency
==> freq. = speed/wavelength = 342.5/0.75 = 456.67 Hz.
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