Question

does this look right

Answer 1

Physics In Action – Week 2 Topics
A farmer finds a strange boulder hidden inside the fields of his land. Curious to know what it is, he calls a friend of his that happen to be a science teacher. When they meet to see the boulder, the teacher tells him not to alter the shape of the boulder until it can be determined where it came from.

The teacher helps him weigh the boulder, and it has a weight of 800 N when placed on a scale with a surface area of 1 m2. The boulder has an irregular shape, so the teacher suggests his friend to place the boulder inside a water tank to see how much the level of water rises from its original volume. The tank had an original volume of water of 5000 L. When the boulder got placed inside the tank, the volume of water rose to 5010.165 L. The teacher was confident that this information could let them know what the boulder was made out of.

Answer 2

Assumptions to consider: ‐ The boulder is a solid and it has a homogeneous mass distribution The water in tank is at room temperature and at standard pressure
‐ Air pressure is standard ‐ Value of gravity used is 10 m/s2
Useful link: http://www.metric ‐conversions.org/conversion‐calculators.htm
Answer the following questions.
All calculation answers require correct metric system units.
In order to receive credit for your answers, all calculation questions REQUIRE THAT YOU SHOW YOUR WORK.

1 – What is the resulting pressure when the boulder is placed on the scale (measured in Pa)?

p = F/A = 800N/1m^2 = 800 N/m^2 = 800 Pa


2 – What scientific principle does the teacher use to find out the volume of the boulder?

Answer 3

If an insoluble, incompressible solid is placed in a fluid, the amount of fluid it displaces equals its own volume.


3 – What is the weight of the displaced amount of water when the boulder is placed inside the tank (measured in N)?

weight of displaced water is: W = rho * V * g = 1.000 kg/l * 10.165 l * 10 N/kg = 101.65 N


4 – What is the density of the boulder (measured in g/cm3)?

density of boulder: rho = m/V = 80 kg/ 10.165 dm^3 = 80 g/10.165 cm^3 = 7.87 g/cm^3




5 –According to the obtained density, what is the element of the periodic table the boulder is made out of? (You can conduct an Internet search to find out!)

in the tables with density elements, the one closest to this one is iron (7.874 g/cm^3)

Answer 4

Assumptions to consider: ‐ The boulder is a solid and it has a homogeneous mass distribution The water in tank is at room temperature and at standard pressure
‐ Air pressure is standard ‐ Value of gravity used is 10 m/s2
Useful link: http://www.metric ‐conversions.org/conversion‐calculators.htm
Answer the following questions.
All calculation answers require correct metric system units.
In order to receive credit for your answers, all calculation questions REQUIRE THAT YOU SHOW YOUR WORK.

1 – What is the resulting pressure when the boulder is placed on the scale (measured in Pa)?

p = F/A = 800N/1m^2 = 800 N/m^2 = 800 Pa


2 – What scientific principle does the teacher use to find out the volume of the boulder?

Answer 5

Yes

Answer 6

quite lengthy seems right to me

Answer 7

You have answered your questions yourself :)