Question

The sensitivity with which an atomic force microscope can measure forces is dependent on the stiffness of the cantilever to which the tip is attached. All else being equal, which would yield a better force sensitivity, a smaller or large cantilever?

Answer 1

Solution:

Let us go to the basics first.

We know that in case of an atomic force microscope, force measurement is dependent on the stiffness of the cantilever to which the tip is attached.

We also know that a smaller cantilever is more stiffer than a longer cantilever. (Reason: A longer cantilever undergoes more deflection at the free end and thus it is less stiffer as compared to smaller cantilever).

As sensitivity of atomic force microscope is directly proportional to stiffness of the cantilever, so a smaller cantilever would yield a better force sensitivity.

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