All physical quantities can be defined in terms of few fundamental physical quantities like Length, Mass and Time. The unit of these fundamental physical quantities or basic quantities are independent of  each other and no one can further resolve it into any other unit. There are 7 basic or fundamental physical quantities. They are Length, Mass, Time, Temperature, Electric Current, Luminous Intensity and Amount of  Substance.

The amplitude of wave is defined as the maximum displacement of any point from its rest or equilibrium position on a wave.

Mathematically,

Amplitude of wave = Maximum displacement.

Dimensional formula of displacement = M⁰L¹T⁰

Putting this value in the above equation we get,

Dimensional Formula of Amplitude of Wave = M⁰L¹T⁰.
SI unit of Amplitude of Wave is metre(m).

Tension is defined as the magnitude of force.

Mathematically,

Tension = Force.
Dimensional Formula of Force= M¹L¹T^-2. [Check how Dimensional Formula of force is derived]

Putting these values in above equation we get,

Dimensional Formula of Tension= M¹L¹T^-2
SI unit of Tension is Newton (N).

Energy is defined as ability to do work.

Mathematically,
Energy = Work.

Dimensional formula of Work = M¹L²T^-2 [Check how Dimensional Formula of work is derived]

Putting these values in above equation we get,
Dimensional Formula of Energy = M¹L²T^-2
SI unit of Energy is Joule (J)

Displacement is defined as change in the position of the particle in a specific direction during a time interval. It is a vector quantity.

The Dimensional Formula of Displacement is M⁰L¹T⁰
SI unit of Displacement is metre (m).