Answer:
[tex]L^{-1}[/tex].
Explanation:
Given that
MM''= a cos(fL)
We know that all trigonometric function are dimensional less.So fL should be dimension less quantity.
Property Dimension
Length L
Mass M
Force [tex]MLT^{-1}[/tex]
Acceleration [tex]LT^{-2}[/tex]
Velocity [tex]LT^{-1}[/tex]
Torque [tex]ML^2T^{-1}[/tex]
Time [tex]T^{-1}[/tex]
So in the given question ,dimension of L is L so the dimension of f will become [tex]L^{-1}[/tex].
