Viscosity

Viscosity

Viscosity is the internal friction between layers of a fluid.

### Formula

$$F=\eta A\frac{dv}{dx}$$

### Terminologies

- F → Viscous force.

- η → Coefficient of viscosity.

- A → Area of layer.

- dv/dx → Velocity gradient.

### SI Unit

$$Pa\,s$$

### Dimensions

$$[\eta]=[ML^{-1}T^{-1}]$$

### Conditions / Special Cases

Higher viscosity means greater resistance to flow.

### Usage

- Used in fluid resistance problems.