What is Density? | Relative Density | Floatation

Density and Relative Density. Flotation Class 9 Physics.

Density and relative density (also known as specific gravity) are both physical properties that describe the compactness or concentration of matter in a substance, typically a solid, liquid, or gas. Density is a measure of how much mass is contained in a given volume of a substance. It is calculated by dividing the mass (m) of a substance by its volume (V).
Density (ρ) = Mass (m) / Volume (V)
Common units for density include kilograms per cubic meter (kg/m³), grams per cubic centimeter (g/cm³). Density is a fundamental property of a material and is used to characterize substances. For example, it can be used to differentiate between different materials based on their mass and volume.
Relative density, often referred to as specific gravity, is a dimensionless quantity that compares the density of a substance to the density of a reference substance, usually water. It tells you how many times denser or lighter a substance is compared to water.
Relative Density (RD or SG) = Density of Substance / Density of Water (at a specified temperature)
Since it is a ratio of densities, it has no units.
Relative density is useful in various applications, especially when comparing the density of a substance to that of water. If the relative density of a substance is less than 1, it is less dense than water and will float on water. If it's greater than 1, it is denser than water and will sink.
For example, if the density of a substance is 2.7 g/cm³, and the density of water is approximately 1 g/cm³, then the relative density of the substance is 2.7. This means the substance is 2.7 times denser than water.
Condition for floatation:
If density of object is greater than the density of liquid ... object will sink
If density of object is less than the density of liquid .... object will float

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[Othniel_Nuamah_Aidoo_Official]

Ships float on water due to the principle of buoyancy. When an object is placed in a fluid (like water), it displaces an amount of fluid equal to its own weight. If the weight of the water displaced is equal to or greater than the weight of the ship, the ship will float. This is achieved by designing ships to be less dense than water, making them buoyant. The shape of the hull also plays a crucial role in providing stability and preventing sinking.

[Mr.SahadevPhysicsMagician]

I am a Physics Teacher, the way you explained is Excellent and very easy to understand.
The activity also Superb and enjoyable in learning.

[ayurgreen]

10:14 this process occurs based on buoyancy as the steel ship has a greater surface area the higher the buoyancy

[rajububanale]

A huge massive ship floats on water but same material ( Steel ) made up of iron sinks because at bottom of ship there is a huge empty space which is filled with air so it makes a huge ship to float on water instead of sinking .

[sriritwikshastry]

To answer :- How Does A Ship float in water when a steel nail sinks?

Answer :- A ship floats on water because it is designed to displace a large amount of water, creating buoyant force greater than its weight. It also has a "LARGER SURFACE AREA". That is why it Floats..
A steel nail sinks because it is denser than water, so the buoyant force is not enough to support its weight.

[akhileshwarbhatt]

I am process Chemist in a sugar plant from 20 years, during processing of juice, clear juice and cane juice mud separated due to density difference in Comercial This is just for me as a refresher course....

[bbbdryj]

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[nggtiqj]

Since the ship is hollaw, it's mostly surrounded by air which is less dense compared to the density of the water in sea /ocean/lake

[raagmuz]

A massive steel ship floats in water based on the concept of Archimedes principle. The area of the steel ship in contact with water in much higher so the buoyancy of water is greater and that is why the massive steel ship floats instead of sinking like the steel nail.

[nagappamallad]

It is because iron made ship displaces a weight of water equal to its own weight, it floats.This is principal of floatation

[bbkvltt]

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[swarnavdasviic]

The volume of the base of the large ship is increased so that it can displace more water as the ship displaces water equal to its volume. The weight of water of the same volume is greater than the weight of ship of same volume. So there's create an up thrust force which causes the ship to sail

[GodduRajukiran-yksg]

Sir please explain about some laws sir like 1)archimedes Principal. 2)Pascal's law 3)Snell's law 4)bernouill's Principal. Sir you have extraordinary talent of teaching

[manjularamesh]

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[FatimaSanyang-upht]

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[nibeditapradhan]

The weight of water displaced by the ship is more than the weight of ship, hence the ship floats; Archemedes Principle

[_cannyswifeu_]

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[EhtishamHaq-dv]

Its basically due to large surface area, since volume is associated with the size and shape so when mass is divided with a large number it will give a small value resulting in less density. Larger surface area or more volume means less density

[dr.scratch]

The reason why ships float is because the relation of Density and Volume is opposite so if volume became bigger therefore the density will become lower and also that's why the ship bottom is almost empty to reduce mass and add more volume to reduce the density which allows it to float (correct me if I am wrong)