Fluid Mechanics: Density & Balances in Beaker B

In summary, if Block A hangs by a cord from a spring balance D and is submerged in a liquid C contained in beaker B, the mass of the beaker is 1.00 kg and the mass of liquid is 1.80 kg. The balances D and E read 3.50 kg and 7.50 kg, respectively. The volume of block A is 3.80 * 10^-3 m^3. If Block A is pulled out of the liquid, the balances D and E will read 3.50 kg and 7.50 kg, respectively.
  • #1
CollectiveRocker
137
0
Block A hangs by a cord from spring balance D and is submerged in a liquid C contained in beaker B. The mass of the beaker is 1.00 kg and the mass of liquid is 1.80 kg. Balance D reads 3.50 kg and balance Balance E( supporting beaker B) reads 7.50 kg. The volume of block A is 3.80 * 10^-3 m^3. a) What is the density of the liquid? b) What will each balance read when Block A is pulled out of liquid? Do I need to know what the liquid is in order to solve this? I know that p(density) = mass/volume. So in this case is it just mass of liquid/volume of liquid?
 
Physics news on Phys.org
  • #2
I suspect that you will need to find the density of the block in order to find the density of the liquid. This can be done by setting up equations for the apparent weight of the block given by balances D and E. Hope that helps.
 
  • #3
Can you please explain further?
 
  • #4
Weight loss/Apparent weight=Weight of body-weight of liquid displaced
weight= mass*g = Volume*density*g.
Need any more help?
regards
 
Last edited:
  • #5
There will be two equations. The first equations will relate the apparent weight of the block given by balance D to the actual weight of the block and the product of the buoyant force (set this up using Archimedes' pricincple). The second equation will relate the weight given by balance E to the weight of beaker B, liquid C and block A. You'll have two equations and two unknowns (one being the density of the block and the other the density of the liquid).
 
  • #6
e(ho0n3 said:
There will be two equations. The first equations will relate the apparent weight of the block given by balance D to the actual weight of the block and the product of the buoyant force (set this up using Archimedes' pricincple). The second equation will relate the weight given by balance E to the weight of beaker B, liquid C and block A. You'll have two equations and two unknowns (one being the density of the block and the other the density of the liquid).


If you don't mind my asking, can you give me the equations?
 
  • #7
CollectiveRocker said:
If you don't mind my asking, can you give me the equations?
Why don't you derive the equations and post them here. Then I'll tell you if you're on the right track.
 
  • #8
w(D) = W(A) * F(B)
W(E) = W(B) + W(liq) + W(A)
 
  • #9
You might want to explain what those symbols mean. Keep in mind Archimedes' principle.
 
  • #10
w(D) = weight read by Balance D
w(A) = weight of Block A
w(B) = weight of Beaker B
w(C) = weight of liquid C
F(B) = bouyant force
 
  • #11
Why in the world are you multiplying w(A) and F(B)? That makes absolutely no sense. Maybe you should go back to the basics.
 
  • #12
solved it. Thanks fellas
 

1. What is density and why is it important in fluid mechanics?

Density is a measure of how much mass is contained in a given volume of a substance. In fluid mechanics, density is important because it determines the buoyancy of a fluid and its ability to flow and exert pressure.

2. How is density calculated in a beaker?

Density is calculated by dividing the mass of the fluid in the beaker by its volume. The mass can be measured using a scale and the volume can be measured using a graduated cylinder or by directly measuring the dimensions of the beaker.

3. What is the purpose of using a balance in fluid mechanics experiments?

A balance is used to measure the mass of the fluid in the beaker. This is important because density is directly related to the mass of the fluid, and accurate measurements are necessary for accurate calculations and analysis.

4. How does the density of a fluid affect its behavior in a beaker?

The density of a fluid affects its behavior in a beaker by determining its buoyancy and its ability to flow and exert pressure. Fluids with higher density will sink in a beaker, while fluids with lower density will float on top of them.

5. What factors can affect the density of a fluid in a beaker?

The density of a fluid in a beaker can be affected by changes in temperature, pressure, and composition. As temperature and pressure increase, the density of a fluid usually decreases. Changes in the composition of the fluid, such as adding solutes, can also affect its density.

Similar threads

Solving the Mystery of the Ball & Beakers: Determining the Layers of Fluids
    • Introductory Physics Homework Help
Replies
7
Views
1K
Block hanging from cord submerged in water, find density
    • Introductory Physics Homework Help
Replies
23
Views
3K
Find Time to Reach Top of Beaker (10 cm)
    • Introductory Physics Homework Help
Replies
16
Views
1K
Density of Liquid: 1667.7kg/m^3 | Solving Buoyancy Q.
    • Introductory Physics Homework Help
Replies
8
Views
2K
Buoyant Force and Archimedes' Principle
    • Introductory Physics Homework Help
Replies
13
Views
2K
Exploring Buoyancy & Balance Scales
    • Introductory Physics Homework Help
Replies
4
Views
2K
Finding the density of a block in two layers of liquids
    • Introductory Physics Homework Help
Replies
6
Views
1K
What are the steps for solving Archimede's principle problems?
    • Introductory Physics Homework Help
Replies
4
Views
17K
Archimedes Principle and hanging block
    • Introductory Physics Homework Help
Replies
25
Views
5K
Fluid Mechanics, Particle Size, Bouyouncy Force
    • Introductory Physics Homework Help
Replies
16
Views
2K

Hot Threads

Recent Insights

Back
Top