A body will experience minimum upthrust when it is completely immersed in

Options

A. turpentine
B. water
C. glycerine
D. mercury

Answer

To solve the question of when a body experiences minimum upthrust when completely immersed in a fluid, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Upthrust**: Upthrust, or buoyant force, is the upward force exerted by a fluid on an object that is submerged in it. According to Archimedes' principle, this force is equal to the weight of the fluid displaced by the object.

2. **Identify the Fluids**: The question suggests considering two fluids: water and glycerin. Water is known for its high fluidity, while glycerin is more viscous.

3. **Analyze Fluid Properties**:
- **Water**: It has a lower density compared to glycerin and allows objects to float easily due to its high fluidity.
- **Glycerin**: It is thicker and more viscous, which means it has a higher density than water. This affects the buoyant force experienced by an object submerged in it.

4. **Compare Upthrust in Both Fluids**:
- When an object is submerged in water, it displaces a significant volume of water, resulting in a considerable upthrust.
- In contrast, when the same object is submerged in glycerin, the volume of glycerin displaced is less effective at providing buoyant force due to its viscosity.

5. **Conclusion**: Based on the properties of the fluids, a body will experience minimum upthrust when it is completely immersed in glycerin. This is because the viscous nature of glycerin reduces the effective buoyant force acting on the object compared to water.

### Final Answer:
A body will experience minimum upthrust when it is completely immersed in glycerin.

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