Physics Chapter on Weight and Buoyancy

Podcast Beta

Play an AI-generated podcast conversation about this lesson

Questions and Answers

Which of the following objects typically float on water?

An empty gallon (correct)

A coin

A rock

Sand

A hollow object will always sink in water.

False

What force opposes the gravitational force when an object is placed in water?

upthrust force

The SI unit of gravitational force is called the __________.

newton Signup and view all the answers

Match the following objects with their characteristic behavior in water:

Tennis ball = Floats Coin = Sinks Ship = Floats Rock = Sinks Signup and view all the answers

What happens to an object if the upthrust force is less than the gravitational force?

The object sinks Signup and view all the answers

Upthrust is associated with the mass of water displaced by an object.

True Signup and view all the answers

Name two examples of hollow objects mentioned.

ships, canoes Signup and view all the answers

What is the SI unit of weight?

Newton (N) Signup and view all the answers

Mass is defined as the quantity of matter in an object.

True Signup and view all the answers

What formula represents the relationship between weight, mass, and acceleration due to gravity?

W = m × g Signup and view all the answers

The SI unit of acceleration due to gravity is ___.

metre per second squared (m/s2) Signup and view all the answers

What would be the weight of an object with a mass of 5 kg if the acceleration due to gravity is 9.8 m/s²?

49 N Signup and view all the answers

If the gravitational force is less than the upthrust force, the object will float.

True Signup and view all the answers

Calculate the weight of an object with a mass of 15 kg and an acceleration due to gravity of 10 m/s².

150 N Signup and view all the answers

Match the terms with their correct definitions:

Weight = Force exerted by gravity on an object Mass = Amount of matter in an object Acceleration due to gravity = Rate of change of velocity due to gravity Upthrust = Force that opposes the weight of an object in fluid Signup and view all the answers

Which of the following objects is likely to sink in water?

Metal spoon Signup and view all the answers

All objects that float on water have a density less than water.

True Signup and view all the answers

What is the definition of density?

Density is the mass of an object divided by its volume. Signup and view all the answers

A ship floats on water while a needle sinks because the ship has a ______ density compared to water.

lower Signup and view all the answers

Match each object with its result in water:

Leaf = Floats Nail = Sinks Plastic spoon = Floats Stone = Sinks Signup and view all the answers

What happens when a part of a submerged bucket is pulled out of the water?

It becomes harder to pull Signup and view all the answers

A porcelain cup floats on water.

False Signup and view all the answers

Name two characteristics of objects that float on water.

They have a lower density than water and displace a volume of water equal to their weight. Signup and view all the answers

What happens to an object if the gravitational force is greater than the upthrust force?

It sinks. Signup and view all the answers

A floating body displaces its weight in water, which is more than its own weight.

False Signup and view all the answers

What is the aim of the experiment to verify the law of floatation?

To prove that a floating body displaces fluid of equal weight to that of the floating body. Signup and view all the answers

The law of floatation states that a floating body displaces its own weight of the __________ in which it floats.

fluid Signup and view all the answers

Which material is NOT mentioned as part of the experiment?

Measuring tape Signup and view all the answers

In the experiment, water is not needed to observe the displacement caused by the wooden blocks.

False Signup and view all the answers

Match the items used in the experiment with their purpose:

Spring balance = Measuring weight Cut plastic bottle = Holding displaced water Eureka Can = Measuring displaced fluid Wooden blocks = Testing floatation principle Signup and view all the answers

What is the procedure for measuring the weight of displaced water?

Immerse a wooden block in the Eureka Can and measure the weight of the cut plastic bottle with displaced water. Signup and view all the answers

What causes an object to float or sink?

Density of the object Signup and view all the answers

If the density of an object is less than that of water, what will happen if you drop the object into water?

It will float. Signup and view all the answers

The density of an object is mass per unit __________.

volume Signup and view all the answers

The submarine sinks in the sea if its density is __________.

greater than that of water Signup and view all the answers

Objects with a higher density than water will always float.

False Signup and view all the answers

State Archimedes’ principle.

An object submerged in a fluid experiences an upward force equal to the weight of the fluid displaced. Signup and view all the answers

Explain how the law of flotation is used in constructing a ship.

The design of a ship is based on ensuring its overall density is less than that of water, allowing it to float. Signup and view all the answers

What is the relationship between the weight of a floating wooden block and the weight of the water displaced when the block is immersed in water?

The weight of the floating wooden block is equal to the weight of the water displaced. Signup and view all the answers

What is the SI unit of weight?

Newton Signup and view all the answers

The formula for calculating weight is W = m + g.

False Signup and view all the answers

What is the relationship between mass and acceleration due to gravity in calculating weight?

Weight is the product of mass and acceleration due to gravity. Signup and view all the answers

The acceleration due to gravity is measured in ______.

meters per second squared Signup and view all the answers

Match the following components with their corresponding values:

Mass of 10 kg = 100 N Acceleration due to gravity of 9.8 m/s² = Weight = 98 N Mass of 5 kg = 50 N Mass of 15 kg with g = 10 m/s² = 150 N Signup and view all the answers

If an object has a mass of 20 kg and the acceleration due to gravity is 9.8 m/s², what is its weight?

196 N Signup and view all the answers

An object will float if the gravitational force is less than the upthrust force.

True Signup and view all the answers

What happens to an object if the upthrust force is equal to the gravitational force?

It remains suspended in the fluid. Signup and view all the answers

An object that has a density greater than that of water will usually:

Sink in water Signup and view all the answers

Kerosene floats on water because it has a higher density than water.

False Signup and view all the answers

What is the formula for calculating density?

Density = Mass / Volume Signup and view all the answers

The SI unit of density is __________.

kilogram per cubic metre (kg/m³) Signup and view all the answers

Match the following objects with their behavior in water:

Metal rod = Sinks Piece of wood = Floats Kerosene = Floats on water Steel = Sinks Signup and view all the answers

If an object has a mass of 500 grams and a volume of 1000 cubic centimeters, what is its density?

0.5 g/cm³ Signup and view all the answers

What happens to an object if its density is less than the fluid it is placed in?

It will float. Signup and view all the answers

Density is defined as the volume of an object per unit mass.

False Signup and view all the answers

What is the density of an object that has a mass of 640 g and a volume of 800 cm³?

0.8 g/cm³ Signup and view all the answers

An object with a density of 10 kg/m³ will float on water.

False Signup and view all the answers

What is the density of water in g/cm³?

1 g/cm³ Signup and view all the answers

The density of an object determines whether it will float or __________ in water.

sink Signup and view all the answers

Match the following mass and volume values with their respective density calculations:

Mass: 1000 kg, Volume: 100 m³ = Density: 10 kg/m³ Mass: 640 g, Volume: 800 cm³ = Density: 0.8 g/cm³ Mass: 2000 g, Volume: 500 cm³ = Density: 4 g/cm³ Mass: 300 kg, Volume: 150 m³ = Density: 2 kg/m³ Signup and view all the answers

Which property allows a ship to float despite being large and heavy?

Low average density Signup and view all the answers

If the density of an object is less than that of water, it will sink.

False Signup and view all the answers

If an object is less dense than water, what will happen when it is placed in water?

It will float. Signup and view all the answers

What is the calculated upthrust when a stone weighs 100 N in air and 80 N in fluid?

20 N Signup and view all the answers

The procedure for verifying Archimedes' principle involves measuring the weight of a stone in the air.

True Signup and view all the answers

What equipment is used to measure the weight of the stone in the described experiment?

spring balance Signup and view all the answers

The law of floatation states that a floating body displaces its own weight of the __________ in which it floats.

fluid Signup and view all the answers

Match the following materials used in the experiment with their purposes:

Spring balance = Measures weight of the stone Eureka Can = Holds water for displacement Plastic bottle = Collects displaced water Thread = Suspends the stone Signup and view all the answers

During the experiment, what is done with the cut plastic bottle tied with thread?

It is used to collect displaced water Signup and view all the answers

The weight of the displaced water is recorded as part of the experiment.

True Signup and view all the answers

The formula for calculating upthrust is: Upthrust = Weight of the stone in the air – Weight of the stone in the __________.

fluid Signup and view all the answers

What occurs when an object floats in water?

It displaces an amount of water equal to the weight of the object. Signup and view all the answers

The upthrust force on an object is always greater than its weight when it floats.

False Signup and view all the answers

What does Archimedes’ principle state?

The upthrust force on an object is equal to the weight of the fluid displaced by the object. Signup and view all the answers

The weight of the displaced water is equal to the __________ force acting on the object.

upthrust Signup and view all the answers

How does the volume of an object submerged in water affect the upthrust force it experiences?

It has no effect on the upthrust force. Signup and view all the answers

Match the concepts with their definitions:

Upthrust force = Weight of the fluid displaced by an object Floating object = Object displacing weight equal to its own weight in fluid Sinking object = Object with greater weight than the fluid displaced Archimedes' principle = Principle explaining buoyancy through fluid displacement Signup and view all the answers

An object that has a density less than that of water will float.

True Signup and view all the answers

When an object sinks in water, it __________ an amount of water equal to its own weight.

displaces Signup and view all the answers

Which of the following objects is likely to float on water?

A balloon Signup and view all the answers

Objects with a higher density than water will always sink.

True Signup and view all the answers

Name one example of an object that sinks in water.

Stone Signup and view all the answers

A __________ will float on water because it has a lower density than water.

canoe Signup and view all the answers

Match the following objects with their floating or sinking behavior:

Balloons = Float Canoes = Float Stones = Sink Glass = Sink Signup and view all the answers

What will happen to an object if the gravitational force is less than the upthrust force?

The object will float. Signup and view all the answers

An object will float if the gravitational force is equal to the upthrust force.

True Signup and view all the answers

Name an object that is likely to float on water from the provided materials.

Feather Signup and view all the answers

The condition for an object to float is that the upthrust force must be __________ the gravitational force.

greater than Signup and view all the answers

Match the following objects with their expected behavior in water:

Nail = Sinks Tennis Ball = Floats Leaf = Floats Stone = Sinks Signup and view all the answers

What happens to a hollow object when placed in water?

It floats because its average density is less than water. Signup and view all the answers

The upthrust force is always greater than the gravitational force for an object to float.

True Signup and view all the answers

What is another name for the gravitational force?

weight Signup and view all the answers

The SI unit of upthrust force is __________.

newton Signup and view all the answers

Match the following objects with their behavior in water:

Tennis ball = Floats Coin = Sinks Ship = Floats Rock = Sinks Signup and view all the answers

What causes an object to sink in water?

Higher density than water Signup and view all the answers

Provide an example of a hollow object that floats.

Boat Signup and view all the answers

Hollow objects are filled with heavy materials to increase their density.

False Signup and view all the answers

What is the principle behind a ship floating on water?

It displaces a volume of water equal to its weight. Signup and view all the answers

The weight of the water displaced by a floating object is always equal to the weight of that object.

True Signup and view all the answers

What happens to the wooden block when it displaces water?

It floats if its weight is less than the weight of the water displaced. Signup and view all the answers

A ship is heavy, but it does not sink in water because the weight of the water displaced is equal to the weight of the __________.

ship Signup and view all the answers

Match the following materials to their purpose in the experiment:

Cut bottle = Measures water displacement Wooden block = Test object for floatation Eureka Can = Collects displaced water Signup and view all the answers

In the context of water transport, how does the law of floatation apply?

It allows vessels to carry heavy weights without sinking. Signup and view all the answers

An object with a weight greater than the weight of the water it displaces will float.

False Signup and view all the answers

What conclusion can be drawn from the experiment verifying the law of floatation?

The weight of the object must equal the weight of the water displaced for it to float. Signup and view all the answers

What happens when an object is placed in water and the upthrust force is equal to the gravitational force?

The object floats. Signup and view all the answers

An object that is more dense than water will always float.

False Signup and view all the answers

What is the relationship between the weight of displaced fluid and the upthrust force on the object?

They are equal. Signup and view all the answers

The law of floatation states that a floating object displaces its own weight of the __________ in which it floats.

fluid Signup and view all the answers

Match the following terms with their definitions:

Upthrust force = The force that opposes the weight of an object submerged in a fluid Displaced water = The volume of water moved aside by a submerged object Gravitational force = The force acting downward on an object due to gravity Floating object = An object that remains on the surface of a fluid Signup and view all the answers

Which factor does NOT affect the magnitude of the upthrust force on a floating object?

The shape of the object Signup and view all the answers

An object sinking in water has a lower density than the fluid.

False Signup and view all the answers

According to Archimedes' principle, the weight of the displaced fluid is equal to the __________ force.

upthrust Signup and view all the answers

Study Notes

Weight and Mass

Weight is the force of gravity on an object and measured in Newtons (N)
Weight is calculated by multiplying mass and acceleration due to gravity (W = m × g)
Mass is the quantity of matter in an object and measured in kilograms (kg)

Floating and Sinking

An object floats on water if the upthrust force is greater than or equal to the gravitational force
Objects with a density less than water float
Hollowed objects are more likely to float because they have a lower density
If the gravitational force is greater than the upthrust force, the object sinks
The upthrust force is associated with the mass of water displaced by a sinking object
The upthrust force acts in the opposite direction of the gravitational force
The gravitational force is also referred to as weight

Archimedes’ Principle

Archimedes' principle states that a floating body displaces its own weight of the fluid in which it floats
It is easier to pull a submerged object from the bottom of a well because the upthrust force assists you
An object is easier to pull as long as the gravitational force is greater than the upthrust force

The Law Of Floatation

The law of floatation can be verified by placing a wooden block in a Eureka Can with the displaced water collected in a bottle
The weight of the displaced water will be equal to the weight of the wooden block
When constructing a ship, the law of floatation is used to ensure that the ship displaces enough water to support its own weight

Gravity, Mass and Weight

The gravitational force is a product of an object's mass (m) and acceleration due to gravity (g)
The SI unit of acceleration due to gravity is meters per second squared (m/s²)
Mass is the quantity of matter in an object and is measured in kilograms (kg)
Gravitational force or weight is represented by W
The SI unit of weight is the newton (N) which is equivalent to kgm/s²
Weight is calculated by multiplying mass and acceleration due to gravity (W = m x g)

Density

Density is the mass of an object per unit volume
The SI unit of density is kilograms per cubic meter ( kg/m³)
The SI unit for density can also be grams per cubic centimeter ( g/cm³)
The density of water is 1 g/cm³ or 1000 kg/m³
Objects that are less dense than water will float
Objects that are more dense than water sink

Archimedes' Principle

When an object is immersed in a fluid, it experiences an upthrust that is equal to the weight of the fluid displaced
The weight of the displaced fluid is equal to the upthrust force
Upthrust is the upward force exerted by a fluid that opposes the weight of an object immersed in it

Buoyancy and Floatation

The magnitude of the upthrust force depends on the volume of the submerged part of the object
For an object to float, the upthrust force must be equal to the gravitational force
If the gravitational force is greater than the upthrust force, the object sinks

Floating and Sinking Objects

Objects with different masses and volumes can either float or sink in water.
Objects like balloons, balls, leaves, and canoes float on water.
Objects like stones, glass, tiles, wax, and some metallic objects sink in water.
The density of an object is a factor in its buoyancy, where a denser object is more likely to sink.
Hollowed objects, like ships, canoes, and empty gallons, float due to their lower average density compared to water.
The upthrust force exerted by water on a floating object is greater than or equal to the gravitational force acting on it.
The upthrust force is related to the volume of water displaced by the object, which relies on the shape and volume of the object.
If the upthrust force is less than the gravitational force, an object will sink.

Archimedes' Principle verification

The weight of an object immersed in water is less than the weight of the object in air.
The weight lost by an object immersed in water is equal to the weight of the water displaced by the object.
The upthrust force acting on an object is equal to the weight of the fluid displaced by that object.

The Law of Floatation

An object floats when its upthrust force, determined by the weight of water it displaces, is equal to the gravitational force acting on it.
The deeper an object is submerged in water, the greater the volume of water it displaces, but the upthrust force remains the same.
The law of floatation is used in designing vessels for water transport.

Application of the Law of Floatation in Water Transport

The law of floatation explains why ships, despite their weight, float on water.
The weight of the ship equals the weight of the water displaced by the submerged portion of the ship.
This demonstrates the fundamental principle that allows objects to float, balancing the forces of weight and buoyancy.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

This quiz covers key concepts related to weight, mass, and buoyancy, including the calculations of gravitational force and the dynamics of floating and sinking. It also explores Archimedes' Principle and its applications in understanding how objects behave in fluids. Test your knowledge and understanding of these fundamental physics principles.