Bulk modulus is the modulus associated with volume strain. The strain equal to the change in volume divided by the original volume is called volume strain. The change in the relative volume of the object when a unit compressive or tensile stress acts on the surface of the object uniformly is called Bulk modulus. The units for the bulk modulus is the pascal. The Bulk modulus helps us understand how an object reacts when compressed from all sides equally.
Bulk modulus formula
K = V(∆P) / ∆V
Where,
K= bulk modulus in pascal
∆P denotes the change in pressure in pascal
∆V denotes the change in volume in m3
V denotes the actual volume of the object in m3