Buoyant force Definition and 142 Threads

Hey guys during my lab i am required to calculate the buoyant force of a liquid so i have to submerge the object in the liquid and take the reading on the balance. after that i have to lower the object to the bottom of the beaker and take the reading again. How are the data going to help in...

Estimate the buoyant force exerted on your body by the air ( use Pair+1.029 kg/m^3). What would be the difference between your weight in the air and your weight in a vacuum? How would I proceed with this? What Equation should I use?

Homework Statement It is hard to imagine that there can be enough air between a book and a table so that there is a net upward (buoyant) force on the book despite the large downward force on the top of the book. About how many air molecules are there between a textbook and a table, if there is...

Homework Statement A cylindrical wooden log is loaded with lead at one end so that it floats upright in water. The length of the submerged portion is L = 2.56m. The log is set into vertical oscillation. (a) Show that the oscillation is simple harmonic (b) Find the period of oscillation...

Homework Statement As shown in the figure below, a wooden cube measuring 20.0 cm on each side floats in water with 90.0% of its volume submerged. Suspended by a string below the wooden cube is a metal cube. The metal cube measures 10.0 cm on each side and has a specific gravity of 6.00. a)...

I did an experiment where i measured the weight (in Newtons) of three objects on a spring scale. Then, i measured the weight (in Newtons) of the three objects on a spring scale while the objects were submerged underwater. How would i calculate the volume and buoyant force?

Homework Statement If you had a rectangular prism and split it in half, half iron, half wood, and let if float on water, would the buoyant force be different on the different sides? The Attempt at a Solution I originally thought since the iron was more dense than the wood, it would...

Homework Statement A rectangular wooden block of weight W floats with exactly one-half of its volume below the waterline. Masses are stacked on top of the block until the top of the block is level with the waterline. This requires 20g of mass. What is the mass of the wooden block? Homework...

Homework Statement William Smith built a small submarine capable of diving as deep as 30.0 m. The submarine's volume can be approximated by that of a cylinder with a length of 3.00 m and a cross-sectional area of 0.500 square meters. Suppose this submarine dives in a freshmwater river and...

Homework Statement The tallest iceberg ever measured stood 167 m above the water. Suppose that both the top and the bottom of this iceberg were flat and the thickness of the submerged part was estimated to be 1.50 km. Calculate the density of ice. The density of sea water equals 1025 kg/m3...

Homework Statement A 2.8 kg rectangular air mattress is 2.00 m long, 0.500 m wide, and 0.100 m thick. What mass can it support in water before sinking? Homework Equations Density = Mass / Volume Magnitude of buoyant force = Weight of fluid displaced Buoyant force = weight of...

Homework Statement 500m long tanker loaded displaces 5.64763x10^8kg water. the tanker is moved to another planet, and it has to displace mercury. What volume of mercury would it displace? and do you need the gravity on that planet? Homework Equations Fb=Fg pf object of subject = P0V0g...

Homework Statement Iceberg area: 3.10x10^4 km^2, Flat top and bottom. Submerged part .84 km. Water density: 1.035x10^3 what is the buoyant force acting on the iceberg? Homework Equations Fb=Fg pf object of subject = P0V0g PfVfg=Weight of displaced fluid=p0v0g=weight of object...

Homework Statement An above-ground backyard swimming pool is shaped like a large hockey puck, with a circular bottom and a vertical wall forming its perimeter. The diameter of the pool is 5.2m and its depth is 1.4m. Find the total outward force exerted on the vertical wall of the pool...

[SOLVED] Basic Buoyant Force HW Question First time doing this, so bare with me:) Homework Statement A 53kg girl dives off a raft 4m square floating in a freshwater lake. By how much does the raft rise? Density of water = 1000kg/m^3 Use the equation for buoyant force. Then solve...

[SOLVED] Buoyant force on a steel boat The bottom of a steel "boat" is a 7.00 m \times 10.0 m \times 4.00 cm piece of steel ( \rho _{{\rm steel}}=7900\;{\rm kg}/{\rm m}^{3}). The sides are made of 0.550 cm-thick steel. What minimum height must the sides have for this boat to float in...

A piece of metal weighs 50 N. in air, 36.0 N in water, and 41.0 in an unknown liquid. Find the densities of the following: The metal The unknown liquid

It's me again. This time I actually understand the material, I just need help with figuring this one out. The tallest iceberg ever measured stood 167 m above the water. Suppose that both the top and bottom of this iceberg were flat and the thickness of the submerged part was estimated to...

Homework Statement (a) What is the buoyant force on 0.70 kg of ice floating freely in liquid water? _____ N upward (b) What is the buoyant force on 0.70 kg of ice that is held completely submerged under water? ______N upward Homework Equations ? The Attempt at a Solution...

I am not sure why this is not clicking... An object hangs from a spring balance. The balance registers 30 N in the air and when it is immersed in water it reads 20 N. What is the buoyant force on this object? Draw a FBD to solve this. FBD...

Homework Statement An object weighing 5.0 Newtons displaces a certain volume of water when dropped into a large beaker of water. The weight of the displaced water is 3.5 Newtons. The object is free to sink or float. What would be the value of the bouyant force is another object twice the...

A 0.5kg block of wood is floating in water. What is the magnitude of buoyant force acting on the block? I know that Fb = (density)(g)(V) The density of water is 1000kg/m3. g = 9.8m/s There is no way i can calculate the volume of the block with the given information. Also i know the water...

A rock with a volume of 0.2m3 is fully sumberged in water with density of 1000kg/m3. What is the buoyant force acting on the rock? Assume that gravity acts on the system 0.2m3*9.81m/s2 = 1.96 buoyant force = 1000kg/m3*1.96 = 1960N ?

I tryied but failed miserabely, i need to prove this formula! Archimedes (Buoyant force) Lets say that a rock is attatched to a string, the string has a tention of 5.0N out of the water, and has a tention of 3.2N submerged in water. Now to find the density of the rock, the formula used...

Homework Statement A helium balloon has volume V0 and temperature T0 at sea level where the pressure is P0 and the air density is \rho_0. The balloon is allowed to float up in the air to altitude y where the temperature is T. (a) Show that the volume occupied by the balloon is then V =...

Homework Statement A 0.5 kg block of wood is floating in water. What is the magnitude of the buoyant force acting on the block. Homework Equations :confused: :confused: :confused: B=Buoyant force: W=weight; fl=fluid; m=mass; V=volume; DEN=density; There are a couple of...

Homework Statement An empty rubber balloon has a mass of .0111 kg. The balloon is filled with helium at 0degrees C, 1atm pressure, and a density of .179 kg/m^3. The filled balloon has a radius of .154 m. What is the magnitude of the buoyant force acting on the balloon? Answer in units of N...

How buoyant force and atmospheric pressure can be helpful in life ?

Homework Statement -A thin spherical shell of mass 0.300 kg and diameter 0.250 m is filled with alcohol ( = 806 kg/m3). It is then released from rest on the bottom of a pool of water. Find the acceleration of the alcohol filled shell as it rises toward the surface of the water. Homework...

Homework Statement Buoyant force. A block of wood floats in oil with 90.0% of its volume submerged. What is the density of oil? The density of the block of wood is 0.67 g/cm3. Homework Equations buoyant force = pgV The Attempt at a Solution p(oil) V(oil)=p(h20) V(h20)...

So there's a wooden block floating on water in such way that 78% of the block is submerged in water. Now oil (with density of 700 kg/m^3) is poured on top so that the wooden block is wholly covered by the oil. Now how much of the block is submerged in water? (Hint: do not ignore the buoyant...

Three children, each of weight 356 N, make a log raft by lashing together logs of diameter 0.30 m and length 1.80 m. How many logs will be needed to keep them afloat in fresh water? Take the density of the logs to be 800 kg/m^3. I'm interpreting this problem as a buoyancy problem for...

buoyant forces I was having trouble with this problem. please let me know how to approach this. thanks. An empty rubber balloon has a mass of 0.0135 kg. The balloon is filled with helium at a density of 0.181 kg/m3. At this density the balloon is spherical with a radius of 0.400 m. If the...

Say I have some volume V of some gas with a pensity P less than the density of air. How can I calculate how much a balloon (of volume V) of this gas could lift? Is this called the "buoyant" force, or is this something else? What I'd like to do is find the find the lifting "power" (...) of some...

70% of a mass is supported by a slab of ice and the ice sinks down so that only half of what was previously exposed now is exposed. What is the mass assuming that the ice has a volume of 10 m^3 and the mass has a specific gravity of 1.0? Why can't I use the buoyant force of the ice before and...

Hi, I am having some trouble with the following question: You (mass 70.1 kg) decide to take off--literally--with a helium balloon of mass 31.6 kg. The densities of air and helium are air = 1.321 kg/m3 and helium = 0.179 kg/m3. What volume of helium is needed to levitate you and the balloon...

Hey This has stumped me and 2 other people who have also tried to solve this problem. My instructor was about to explain it but just left us with we can get it through the equation of Buoyant force Bf=pgv. Here is the actual question from my book. I have no idea how your supposed to...

I've already determined the first part of the question, which is regarding the buoyant force. An object weights 5N and displaces 3.5 N of water when placed in the beaker. The buoyant force is = to the displaced water which is 3.5N. Now, here's where I'm stuck. The volume doubles, and weight...

Is this a correct interpretation of Archimedes Principle for this application? A balloon is filled with helium (density = .02 kg/m^3) and has a volume of .009 m^3. What is the buoyant force exerted on the balloon in air (density = 1.3 km/m^3)? Fb = (1.3 km/m^3)x (.009 m^3) x (9.80 m)...

A hollow, plastic sphere is held below the surface of a freshwater lake by a cord anchored to the bottom of the lake. The sphere has a volume of 0.700 M^3 and the tension in the cord is 760 N. Calculate the buoyant force exerted by the water on the sphere. Take the density of water to be 1000...

If two objects are the same shape and have the same dimensions, but one object has a bigger density, does that affect the buoyant force? Will the object with a bigger density have a greater buoyant force? They're both immersed in water. I say no because the buoyant force depends on the...

I'm really fired up about physics now. But I can't puzzle out the following: Q. When you float in fresh water, the buoyant force that acts on you is equal to your weight. When you float higher in the high-density water of Salt Lake, the B.F. that acts on you is actually: 1) greater than your...