Question
Having trouble with these problems. I just want to make sure I did them right. Thanks !
Increasing the size of an object while maintaining the same mass increases / decreases / doesn't change the object's density (circle one) An object with a density of .67 kg/L would float 1/3 , 1/2, 2/3 under water, (circle one) A floating object has an upward buoyant force that is equal to/larger than/less than the downward weight. An ice cube dropped into a glass of 100% ethanol (density= .789 kg/L) would sink / float. Using the formula you found relating density and the percent submerged, determine the percentage of a wood block (p=.400 kg/L) that would be submerged in ethanol. Determine the density of an unknown metal that displaces 4.5 L of water and is found to have a mass of 25.4 kg. How much water will a 1.00 kg metal block displace with a density of 7.00 kg/L? How much water will a 1.00 kg plastic block (rho= 0.60 kg/L) displace when floating? (careful) Imagine holding the above plastic block under water. When released, what is the upward acceleration of the block? (use g = 10 m/s2) What is the relationship between the buoyant force and the weight of an object when the object: a. Sinks b. Floats c. Hovers in the fluid How is it possible to have two objects of the same mass where One object sinks and the other object floats? Use your observations to answer this question. Give a brief description of what the relationship is between mass, volume and density of an object and how density affects whether the object will sink or float.
Explanation / Answer
1. Decreases
2. 2/3
3. Larger than
4. Sink
5. 50.7%
6. 5.644 kg/L
7.142.857 grams (.142857 Liters)
8. 1 Liter
9. 6.667 m/s
10. Sinks: bouyant force< weight Floats:bouyant force >weight Hovers: bouyant force = weight
11. The volume the object occupies can differ, where one displaces more fluid than the other, due to it having a lower density while having the same mass.
12. Density = Mass/Volume and if the density of an object is less than the density of the fluid it is in, it will float, if it is less than it will sink, and if the densities are equal, the object will hover in the fluid
