- #1
Delhi
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Hello, I would like to ask if my calculations are correct and which approach I should use if the answer is correct (I apologize if my calculations look ugly, just joined this forum).
On land, the maximum weight of a concrete block you can carry is 25kg. How massive block could you carry underwater, if the density of concrete is 2200kg/m³?
pwater = 1000 kg/m³
pconcrete = 2200 kg/m³
m1 = 25 kg
m2 = ?
G = mg
g = 9,81 m/s²
Archimedes' Principle
Fapplied - G + Fbuoyancy = 0
G - Fbuoyancy
Approach 1:
Fapplied - G + Fbuoyancy = 0 ->
m1g - m2g + m2pwaterg / pconcrete = 0
And I come to this:
m2 = -m1 / ( (pwater/pconcrete) - 1 )
m2 = 45,8333... kg
Approach 2:
On land I need (F= mg) 245,25 N to carry the concrete block
G - Fbouyancy = 245,25 N
m2g - m2g(pwater / pconcrete) = 245,25N
m2g(1 - pwater / pconcrete) = 245,25 N
m2 = 245,25N / g(1 - pwater / pconcrete)
m2 = 45,8333... kg
Homework Statement
On land, the maximum weight of a concrete block you can carry is 25kg. How massive block could you carry underwater, if the density of concrete is 2200kg/m³?
pwater = 1000 kg/m³
pconcrete = 2200 kg/m³
m1 = 25 kg
m2 = ?
G = mg
g = 9,81 m/s²
Homework Equations
Archimedes' Principle
Fapplied - G + Fbuoyancy = 0
G - Fbuoyancy
The Attempt at a Solution
Approach 1:
Fapplied - G + Fbuoyancy = 0 ->
m1g - m2g + m2pwaterg / pconcrete = 0
And I come to this:
m2 = -m1 / ( (pwater/pconcrete) - 1 )
m2 = 45,8333... kg
Approach 2:
On land I need (F= mg) 245,25 N to carry the concrete block
G - Fbouyancy = 245,25 N
m2g - m2g(pwater / pconcrete) = 245,25N
m2g(1 - pwater / pconcrete) = 245,25 N
m2 = 245,25N / g(1 - pwater / pconcrete)
m2 = 45,8333... kg