Determine the density at which it sinks -- experiment

AI Thread Summary
To determine the density at which an object sinks, it must be denser than the fluid it is placed in. The online simulation allows for adjusting the fluid's density but not the object's density, complicating the lab report. The key concept is that an object will sink when its density exceeds that of the fluid, while it remains neutrally buoyant when densities match. The challenge lies in filling out the lab report table accurately, given the limitations of the simulation. Clarification from the lab author may be necessary for precise instructions on completing the assignment.
neverlnd
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Homework Statement



Hello :) This is a last resort. I'm stuck on what to do to complete this lab report table.

We are required to conduct an online simulation at this link: Buoyancy Online Simulation
This is the document of the lab report I'm required to fill up (I'm stuck at part 2)

Homework Equations



  1. For each of the objects, determine the density at which it sinks in kg/L What does this mean? :(
  2. Use a mass of 4.5 kg.
  3. List this value in the table

The Attempt at a Solution


For ease, a picture of the table and what I've done so far - My understanding is "what does the density of the object need to be in order to sink". So the object has to be at minimum, denser than the liquid in order to sink. Is this completely wrong? :/This is a time limited request because the deadline is about 12 hours away ( like I said, this is a last resort as I am totally stumped and my instructor is not replying any of my emails since the start of the week :/ )

Thank you in advance !
 
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Hi neverlnd,

Welcome to Physics Forums.

I took a quick look at the simulator and its options, and there doesn't appear to be any way to adjust the densities of the individual objects other than the "My Block". The only variable density I can find when one of the listed objects is in play is that of the fluid, which is continuously adjustable. But the table for part 2 has columns for all the specific fluids. So, as you've found, it's hard to tell what the lab author had in mind for this part of the lab.

You're right that a given block will sink when its density is greater than that of the fluid. It will be neutrally buoyant if the densities match (which means you could place the object under the surface and will stay where you put it).

I'm afraid I can't think of a way to fill out every entry in the given table that would make sense. If the table had only one column I'd say list the fluid density at which the given block would just sink, the neutral buoyancy being the threshold value.
 
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