(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

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Buoyancy Formula (Fb, mdg, T etc)

**Physics Forums | Science Articles, Homework Help, Discussion**