A solid rock, suspended in air by a spring scale, has a measured mass of 8.00 kg

Physics
Tutor: None Selected Time limit: 1 Day

A solid rock, suspended in air by a spring scale, has a measured mass of 8.00 kg. When the rock is submerged in water, the scale reads 3.70 kg. What is the density of the rock? (water density = 1 000 kg/m3)

Jun 28th, 2015

Thank you for the opportunity to help you with your question!

This Question is currently still in progress and will be finished shortly


Please find the solution enclosed here with .. In case of any doubt please feel free to ask… Do not forget to best my answer… If you are having some other problem please feel free to contact me for quick & quality services..
Jun 28th, 2015

Volume of water displaced by the rock is equal to the rock’s volume (Archimedes principle),

From Newton’s 2nd law, the equation for the net forces acting on the rock in air is:   0 = w(air) - mg
mg =w(air)---------------------(1)

Force  for the rock in water  0 = B - mg + w(water)
B = mg - w(water)----------------(2)

From 1 & 2 we can write ,  B = w(air) - w(water)  = (8.00) * (9.80) - (3.7 kg)*(9.80)  = 42.14 N

Since buoyancy B = ρVg
V = B / ρg  = 42.14 / (1000*9.80 ) = 0.0043 m³

  Hence volume of the rock = 0.0043 m³ , therefore density of the rock is, ρ = 8 / 0.0043 =  1860.465 kg/m³

Jun 28th, 2015

a.

0.68 × 103 kg/m3

b.

0.86 × 103 kg/m3

c.

1.86 × 103 kg/m3

d.

​2.36× 103 kg/m3

e.

0.32 × 103 kg/m3


Jun 28th, 2015

option C

Jun 28th, 2015

Did you know? You can earn $20 for every friend you invite to Studypool!
Click here to
Refer a Friend
...
Jun 28th, 2015
...
Jun 28th, 2015
Dec 8th, 2016
check_circle
Mark as Final Answer
check_circle
Unmark as Final Answer
check_circle
Final Answer

Secure Information

Content will be erased after question is completed.

check_circle
Final Answer