UPTHRUST AND DENSITY JS3 E-NOT
By the end of the lesion the students should be able to
Explain the term Up Thrust and Density.
State the Archimedes Principle and Law of Flotation,
Establish the Different Between Up Thrust and Density
EXPLANATION IN DETAILS:
“Upthrust” is a term commonly used in physics, specifically in the context of fluid mechanics or buoyancy. It refers to the upward force exerted by a fluid on an object placed in it or submerged in it. This force is a result of the pressure difference between the top and bottom of the object.
UPTHRUST AND DENSITY JS3 E-NOT
When an object is placed in a fluid (liquid or gas), it displaces some of the fluid. The fluid exerts pressure on the object from all directions. However, the pressure increases with depth due to the weight of the fluid above it. This results in a higher pressure at the bottom of the object compared to the top. The pressure difference between the top and bottom creates an upward force, known as upthrust or buoyant force.
Density, on the other hand, is a measure of how much mass is contained in a given volume of a substance. It is usually expressed in units such as kilograms per cubic meter (kg/m³) or grams per cubic centimeter (g/cm³).
The relationship between upthrust and density is fundamental to understanding buoyancy. Archimedes’ principle states that the buoyant force acting on an object submerged in a fluid is equal to the weight of the fluid displaced by the object. This buoyant force depends on the density of the fluid and the volume of the displaced fluid.
The density of an object also plays a crucial role. If the object’s density is greater than that of the fluid, it will sink as the upthrust will be less than its weight. If the object’s density is less than that of the fluid, it will float as the upthrust will exceed its weight. And if the object’s density is equal to that of the fluid, it will remain suspended at a certain level within the fluid.
So, in summary, upthrust is the upward force exerted by a fluid on an object, and density is a measure of how tightly packed the mass within a substance is. The interplay between these two concepts explains why objects sink or float in fluids.
What Is Up Thrust
Upthrust: Upthrust, also known as buoyant force, is the upward force exerted by a fluid (liquid or gas) on an object placed in it or submerged in it. It occurs due to the pressure difference between the top and bottom of the object within the fluid.
What Is Density
Density: Density is a measure of how much mass is contained in a given volume of a substance. It is usually expressed in units such as kilograms per cubic meter (kg/m³) or grams per cubic centimeter (g/cm³).
STATE THE ARCHIMEDES PRINCIPLE AND LAW OF FLOTATION:
ARCHIMEDES’ PRINCIPLE:
Archimedes’ principle states that the buoyant force acting on an object submerged in a fluid is equal to the weight of the fluid displaced by the object. In simpler terms, the buoyant force experienced by an object in a fluid is equal to the weight of the fluid that the object displaces.
LAW OF FLOTATION:
The law of flotation states that a floating object displaces its own weight of the fluid in which it floats. In other words, the weight of the fluid displaced by the floating object is equal to the weight of the object itself.
DIFFERENT BETWEEN UP THRUST AND DENSITY
Definition: Upthrust is a force exerted by a fluid on an object immersed in it, whereas density is a property of matter, describing how much mass is packed into a given volume.
Nature: Upthrust is a force, while density is a property.
Cause: Upthrust is caused by the pressure difference within a fluid, while density is an intrinsic property of a substance.
Measurement: Upthrust is measured in force units (such as Newtons), while density is measured in mass per unit volume (such as kg/m³ or g/cm³).
In summary, upthrust is the force exerted by a fluid on an object, while density is a property of the object itself. The relationship between these two concepts explains why objects sink or float in fluids, as described by Archimedes’ principle and the law of flotation.
OBJECTIVE QUESTIONS
What is upthrust?
- a) A push or pull
- b) A downward force
- c) An upward force
- d) A sideways force
Which of the following objects will float in water?
- a) A rock
- b) A steel nail
- c) A wooden stick
- d) A coin
What is density?
- a) How fast an object moves
- b) The amount of space an object takes up
- c) The amount of mass in a given volume
- d) The color of an object
What happens to an object if its density is less than the density of water?
- a) It sinks
- b) It floats
- c) It dissolves
- d) It evaporates
Which of the following is an example of upthrust?
- a) A bird flying in the sky
- b) A boat floating on a river
- c) A car driving on a road
- d) A plane taking off
Why does a balloon filled with air float in water?
- a) Because it is heavier than water
- b) Because it has less density than water
- c) Because it has more density than water
- d) Because it is pushed down by air
What causes an object to sink in a liquid?
- a) If it has less mass
- b) If it has more volume
- c) If its density is greater than the liquid’s density
- d) If its shape is flat
What unit is commonly used to measure density?
- a) Kilograms (kg)
- b) Grams per cubic centimeter (g/cm³)
- c) Liters (L)
- d) Meters per second (m/s)
An object will sink in water if
- a) It is heavy
- b) It is light
- c) Its density is more than water
- d) Its density is less than water
Which of these materials has the highest density?
- a) Wood
- b) Water
- c) Iron
- d) Oil
What do we call the force that pushes objects up in a fluid?
- a) Gravity
- b) Upthrust
- c) Friction
- d) Tension
If a stone is dropped in a glass of water, it will:
- a) Float
- b) Sink
- c) Evaporate
- d) Dissolve
What happens to a piece of wood placed in water?
- a) It sinks
- b) It floats
- c) It dissolves
- d) It stays suspended
What is the main factor that determines whether an object will float or sink in water?
- a) Color of the object
- b) Shape of the object
- c) Density of the object
- d) Size of the object
Which of the following will NOT affect the upthrust on an object in water?
- a) The volume of the object
- b) The density of the object
- c) The shape of the object
- d) The density of the water
If you put oil in water, what will happen?
- a) Oil will sink
- b) Oil will float
- c) Oil will dissolve
- d) Oil will change color
Why does ice float on water?
- a) Because it is heavier
- b) Because it has less density
- c) Because it is colder
- d) Because it has more density
An empty plastic bottle will float on water because:
- a) It has high density
- b) It has low density
- c) It is heavy
- d) It is filled with air
What is the effect of upthrust on a submerged object?
- a) It pushes the object down
- b) It makes the object dissolve
- c) It pushes the object up
- d) It pulls the object sideways
Which of these is true about objects with higher density than water?
- a) They float in water
- b) They sink in water
- c) They float in air
- d) They evaporate in water
Theory Questions
Explain what upthrust is and describe a situation where you can observe it.
Define density and explain how it determines whether an object will float or sink in water.
Discuss why a metal ship can float in water even though metal is denser than water.
Describe an experiment to measure the density of a small object.
Explain why icebergs float on the ocean, considering the concepts of upthrust and density.
Feel free to let me know if you need more questions or any further details!
You Can Get In Touch With Me On: +2348076206066 OR What’s-app On +2348102326329.
