Physics second exam

One is a property that gas and liquid have?

They can flow which means they can alter their shape

Substances that can alter there shapes are called?

Fluids

Why are solid objects not considered as fluids?

Beacuse they ave s definite shape

Even though gases and liwuids has similarities what are the things that makes them dif?

Having an undefinite volume gas

What is the charastrictic that shares between both liquids and solids and gases and liquids?

Liquids has a definite volume so does solids

Liquids has a undefinet shape so does gases

How ever gases? That means?

Donot have a definite volume or definite shape

If u pour it into a container it will take the shape of it and spread to fill the container

An example?

Pouring water into a glass

Density? Its def?

Its how much there is of a quantity in a given amount of space

Its mass per a unit volume of a subtstance

When the word density is used to describe a fluid what is really being measured is?

Its often represented by?

Mass density

The greek letter (rho) P

Solid and liquids relation to pressure and gases?

Solid and liquids are? Which means which states?

What about gases?

Solid and liquid are almost incompressible that means they are indenpendent of pressure

And there density changes very littile when pressure is added

Gases are compresible which means there densities vary over a wide range of values

Thus it means

But for temperature?

there isnt a standared density for gas but there is for liquid and solids

But when the temperature changes the density changes over a long value

Why are objects lighter in water?

Objects that sink?

The weight of an object immersed in a fluid is called?

Then why do things sink?

Beacuse there is a force thats is the opposite of gravity

Have a net force on them that is smaller than its weight

Its called its apparent weight

Bewcuse there weight is larger than the netforce exerted by the bouyant force

Buoyant force

A force that acts upward on an object submerged in a liquid or floating on the liquids surface

Displaced volume?

Its the total volume of water that collects in the small container is the displaced volume of water from the large container

Displaced volume is =

The magnitude of bouyant force acting on a brick at any given time can be calculated by?

To the volume of the brick

Archimidies principle

What does archimidiese principle state?

Any object completly or partially submerged in a fluid expriences an upward bouyant force equal in magnitude to the weight of the fluid displaced by the object

Archimidies principle law?

Whether an object will float or sink depends

That netforce is the ?

The fluid quantities come from?

Fb=Fg=mass of the displaced fluid x gravitational acceleration

The netforce exerted on it

Objects apparent weight

The displaced fluid

For s floating object the bouyant force is equal to

Which means that are at?

When is archimidies principle not needed?

The objects weight

Equalibirum

To find the bouyant force of a floating object when the weight is known

The density of an object determines?

That means?

When an object floats on a fluid its net force is? beacuse its the minus of the two densities when they are equal its zero

The displaced volume can never be greater?

So for an object to float?

The depth of submersion

The higher the density the more its submerged

0

Than the objects volume

The objects density cannever be greater than the fluids density

Volume of before and fluid is equal to? So if the densities sre equal to one?

Bouyancy can be changed?

For example?

The ratios of the densities

The ibject will be submerged but wont sink

By changing average density

A submarine realeases pumps of air to get back to the surface

Why does a cargo float?

Beacuse there bouyant force and object weight are balanced

The apparent weight of a?

Submerged object depends on the density

When a raft sinks? The net force is equal to?

The vector sum of the bouyant force and the weight of the raft and cargo

When is it negative?

When is it positeve?

When is it submerged but not sinked?

If the objects density ks greater than the fluids density the netforce will be negative and the object sinks

If the objects density is less than the fluids density the net force is positive and the object floats

But if the densitys are the same the object is submerged but doesnt sink

Bouyancy is equal to the weight of the object when it floats beacuse?

Its at equalibrium and equalibirum has a netforce of 0