What is the mass of a floating block of wood in oil and water?

AI Thread Summary
To determine the mass of a cubical block of wood floating at the interface between oil and water, the block's dimensions and the densities of both fluids are crucial. The block, measuring 10 cm on each side, has its lower surface 2 cm submerged in water, meaning 8 cm is in oil. The relevant formula involves calculating the buoyant force, which equals the weight of the displaced fluids. The confusion arises from the total height of the fluids in the container, but only the submerged volume affects the calculations. Ultimately, the mass of the block can be derived from the buoyant force exerted by the oil and water.
laurenh19
Messages
2
Reaction score
0
i have a physics problem about buoyancy and could really use some help!
a cubical block of wood 10cm on a side, floats at the interface between oil and water with the lower surface 2cm below the interface. the density of oil is 0.6 g/cm^3 and the density of water is 1.00g/cm^3. what is the mass of the block?
it also has a picture that shows that the container is filled with 10cm of oil on top of 10 cm of water.


force=(density)(volume)(gravity)


i have no idea where to even begin!
 
Physics news on Phys.org
If half the volume of the block was below the boundary (5cm below) the block would have a density half way between that of oil and water (i.e 0.8 g/cm^3). From the density you could easily calculate the mass, try using the same argument for the numbers in your question.
 
i'm confused on why they would say that the container is 10cm full with oil and 10 cm full with water...do i have to add that into my calculations somewhere?

so far I've come up with

mass=(0.6g/cm3)(8cm)+(1.00g/cm3)(2cm)
 
Thread 'Collision of a bullet on a rod-string system: query'

Thread 'Collision of a bullet on a rod-string system: query'

In this question, I have a question. I am NOT trying to solve it, but it is just a conceptual question. Consider the point on the rod, which connects the string and the rod. My question: just before and after the collision, is ANGULAR momentum CONSERVED about this point? Lets call the point which connects the string and rod as P. Why am I asking this? : it is clear from the scenario that the point of concern, which connects the string and the rod, moves in a circular path due to the string...
View full post »
Thread 'A cylinder connected to a hanged mass'

Thread 'A cylinder connected to a hanged mass'

Let's declare that for the cylinder, mass = M = 10 kg Radius = R = 4 m For the wall and the floor, Friction coeff = ##\mu## = 0.5 For the hanging mass, mass = m = 11 kg First, we divide the force according to their respective plane (x and y thing, correct me if I'm wrong) and according to which, cylinder or the hanging mass, they're working on. Force on the hanging mass $$mg - T = ma$$ Force(Cylinder) on y $$N_f + f_w - Mg = 0$$ Force(Cylinder) on x $$T + f_f - N_w = Ma$$ There's also...
View full post »

Similar threads

Finding the density of a block in two layers of liquids
Replies
6
Views
2K
Fluids, mass of object floating over oil above water
Replies
10
Views
2K
Object floating on water with oil poured in
Replies
13
Views
12K
Block floating in between oil and water, what's the FBD?
Replies
21
Views
20K
Calculating Buoyancy Force & Length of Submerged Cube
Replies
11
Views
2K
Buoyant Force and Archimedes' Principle
Replies
13
Views
3K
How does oil affect the buoyant force of a block of wood versus water?
Replies
1
Views
6K
Fluid mechanics,wooden block in water and oil
Replies
1
Views
2K
Aluminium weight buoyancy problem
Replies
2
Views
2K
Buoyancy, depth a block will sink in two different liquids
Replies
16
Views
4K

Hot Threads

Recent Insights

Back
Top