Register to reply

Does the buoyant force change in different fluids?

by jayadds
Tags: buoyant, fluids, force
Share this thread:
Mar16-12, 02:00 AM
P: 42
Given two objects of identical density and weight, one is floating on water and the other is floating on saltwater. Is the magnitude of buoyant force acting on the object the same in the two situations? From my thinking, it seems that the weight of the object in the the two situations should not change and so the buoyant force should not change as well (Archimedes principle). Correct me if I'm wrong in that thinking.

Phys.Org News Partner Physics news on
Refocusing research into high-temperature superconductors
Neutron tomography technique reveals phase fractions of crystalline materials in 3-dimensions
Tiny magnets, huge fields: Nanoscale ferromagnetic electrodes create chemical equivalent of solid-state spin valve
Michael C
Mar16-12, 03:16 AM
P: 132
If both objects are floating in equilibrium, the upwards force on each object (buoyant force) must be equal to the downwards force (weight), so you are correct.

The buoyant force is equal to the weight of the amount of fluid displaced, so the object floating on saltwater will displace less fluid and therefore float higher than the object floating on pure water.
Mar16-12, 10:02 AM
P: 774
However, if the object was fully immersed in water, then the bouyant force WOULD be different.

Register to reply

Related Discussions
Buoyant Force Classical Physics 1
Buoyant Force and Massive G force protection? Classical Physics 1
Buoyant force of pool (fluids) Introductory Physics Homework 1
Buoyant force Introductory Physics Homework 9
Physics fluids - buoyant principle help Introductory Physics Homework 2