(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Hi Everyone! I'm new to this forum and a beginner at physics so I hope to get some help! :-)

I am doing a report for a lab we did a few weeks ago, and it happens to be one where I was feeling awful and obviously not paying enough attention!

We were using a rubber duck with a weight, submurging it in water and measuring the mass and volume of the duck and then finding its mean density.

The mass of the duck = 70g

The mass of the weight used = 30g

One of the questions asks:

"Write an equation relating the buoyant force B, gravitational force mdg on ducky, the tension downward due to the small force of weight W and the tension T upward provided by the string and spring balance. Use this equation and the measurements of T and W and ducky's mass md to deduce the buoyand force and hence the volume of water displaced"

3. The attempt at a solution

Now, I have an equation at the bottom of my page that says the volume of the water is 1x10-4L and the density of the duck is (0.07)(1.10-4) = 700 kgl-3

And another that says the weight of the duck is .686N.

Do these sound correct? And what would be the equation they are asking for above?

Maybe I shouldn't do these assignments so late at night, but I feel at bit lost! lol

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# Homework Help: Buoyancy Formula (Fb, mdg, T etc)

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