(adsbygoogle = window.adsbygoogle || []).push({}); 1. A wooden ball with a weight of 14.0 N hangs from a string tied to a spring scale. When the ball is at rest, exactly 50% submerged in water, the spring scale reads 5.00 N. For this problem, we will use a density of water of 1000 kg/m3, and we will use g = 10.0 m/s2.

(a) If the ball was only 20.0% submerged in water instead, what would the spring scale read?

(b) Determine the density of the ball.

(c) Determine the volume of the ball.

2. Archimede's Principle

3. I was able to find the answer to part A by applying Newton's second law on the forces acting on the wooden ball. Using the buoyant force from the given and the percentage of submergence, I set a proportion finding the buoyant force for the new percentage of submergence and resulted in 3.6 N. Since the scale measures the tension in the spring, tension would be mg-buoyant force.

However, I am having troubles with part b and c. Using Archimede's principle of buoyant force = density of fluid * volume displaced* g, I resulted in volume displaced of 3.6 E-4 cubic meters. Using a derivative of the equation, density of fluid*volume displaced=density of object*volume of object, I set the volume displaced/volume of object as 0.2, since that is the percentage of the object submerged and resulted in a object volume of 0.0018 cubic meters. Using this proportion of 0.2 as equal to density of object/density of fluid, I resulted in a object density of 200 kg/cubic meters. However, these answers were incorrect.

Any advice will be appreciated.

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# Homework Help: Buoyancy Problem Involving Archimede's Principle

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