Difference between MASS and WEIGHT

MooMooMath and Science

27 Dec 201903:19

Summary

TLDRThis educational video script from moomoomath and science explores the distinction between mass and weight. It explains that mass, measured in kilograms, is the amount of matter in an object, while weight is the gravitational force exerted on it, measured in Newtons. The script clarifies that an object's mass remains constant regardless of its location, but its weight varies due to differences in gravitational pull, such as on Earth, the Moon, Mars, and Jupiter. The video concludes by emphasizing the importance of understanding these fundamental concepts in physics.

Takeaways

📚 Mass and weight are not the same thing; mass is a measure of the amount of matter in an object, while weight is the force of gravitational attraction.
🔍 Mass is measured using a balance by comparing it to a known amount of matter, whereas weight is measured using a scale.
🌍 The mass of an object remains constant regardless of its location, but its weight changes depending on the gravitational pull of the environment.
📏 The SI unit for mass is the kilogram, which was originally defined based on the mass of one liter of water.
🌕 In the imperial system, the unit for mass is the slug, which is equivalent to 32 pounds.
🌐 Weight is technically a force and should be measured in Newtons, where 1 Newton is the force that gives a 1 kg mass an acceleration of 1 meter per second squared.
🌗 The imperial system uses pounds to measure weight, with one pound defined as 0.45359237 kilograms.
🌕 On Earth, an object with a mass of 1 kilogram has a weight of about 9.8 Newtons, but this weight varies on other celestial bodies like the Moon.
🚀 If an object has a mass of 90.91 kilograms and a weight of 200 pounds on Earth, it would weigh 32 pounds on the Moon, maintaining the same mass.
🪐 On different planets like Mars and Jupiter, the weight of the same object changes due to different gravitational forces, but its mass remains constant.

Q & A

What is the difference between mass and weight?
-Mass is the amount of matter an object contains, while weight is the force of gravitational attraction an object feels towards another object, like the Earth's center.
How is mass measured?
-Mass is measured using a balance, which compares a known amount of matter to an unknown amount of matter.
Does the mass of an object change when its location changes?
-No, the mass of an object remains constant regardless of its location.
How does weight differ from mass in terms of location?
-Weight changes with location because it is influenced by the gravitational pull of different celestial bodies.
What is the SI unit for mass?
-The SI unit for mass is the kilogram.
What was the original definition of a kilogram in 1795?
-The kilogram was originally defined as the amount of mass of one liter of water.
What is the unit for mass in the imperial system?
-In the imperial system, the unit for mass is the slug, which has a mass of 32 pounds.
How is weight technically measured?
-Weight is technically measured in Newtons, as it is a measure of the force that gravity is pulling on an object.
What is the weight of an object with a mass of 1 kilogram on the surface of the Earth?
-An object with a mass of 1 kilogram has a weight of about 9.8 Newtons on the surface of the Earth.
How does the weight of an object change on the moon compared to Earth?
-The weight of an object on the moon is about one-sixth of its weight on Earth due to the moon's weaker gravitational pull.
What would be the weight of a 90.91-kilogram cube on Mars?
-A 90.91-kilogram cube would weigh 76 pounds on Mars, but its mass would remain the same at 90.91 kilograms.
How does the weight of an object change on Jupiter?
-On Jupiter, the weight of an object increases due to its stronger gravitational pull compared to Earth.

Outlines

00:00

📚 Understanding Mass and Weight

This paragraph explains the difference between mass and weight. Mass is the amount of matter in an object, while weight is the force exerted by gravity on that object. Mass is measured using a balance and remains constant regardless of location, whereas weight changes with location due to varying gravitational forces. The SI unit for mass is the kilogram, and for weight, it's the Newton. The paragraph also clarifies that while weight can vary on different celestial bodies, mass remains the same. For instance, an object with a mass of 1 kilogram has a weight of about 9.8 Newtons on Earth, but only one-sixth as much on the moon.

Mindmap

Keywords

💡Mass

Mass refers to the amount of matter contained in an object. It is a fundamental property that does not change regardless of the object's location in the universe. In the video, mass is defined as the 'amount of matter an object contains' and is measured using a balance by comparing it to a known amount of matter. The SI unit for mass is the kilogram, which was originally defined based on the mass of one liter of water. The video also mentions the slug as the unit of mass in the imperial system, equivalent to 32 pounds.

💡Weight

Weight is the force exerted on an object due to gravitational attraction. It is different from mass because it varies depending on the strength of the gravitational field. The video clarifies that while mass remains constant, 'weight changes with location'. On Earth, weight is commonly measured in pounds, but it can change significantly on other celestial bodies like the Moon or Mars due to differences in gravitational pull. The video uses the example of an object with a mass of 1 kilogram having a weight of about 9.8 Newtons on Earth.

💡Gravitational Attraction

Gravitational attraction is the force that attracts two bodies towards each other. In the context of the video, it is the force that causes weight, as it pulls objects towards the center of the Earth or other celestial bodies. The video explains that gravity is what gives an object weight, and this force is what varies across different planets, affecting the weight of an object but not its mass.

💡Newton

A Newton is the SI unit of force, defined as the force required to accelerate a one-kilogram mass by one meter per second squared. The video uses this unit to illustrate the concept of weight, stating that an object with a mass of 1 kilogram has a weight of about 9.8 Newtons on the Earth's surface. This unit helps to quantify the force of gravity acting on an object.

💡Pound

The pound is a unit of weight in the imperial system, defined in terms of the kilogram as exactly 0.45359237 kilograms. The video mentions that the pound is used to measure weight, contrasting it with the kilogram, which is a unit of mass. It gives the example that if a person weighs 161 pounds on Earth, their mass would be 5 slugs.

💡Slug

A slug is a unit of mass in the imperial system, defined as the mass that will accelerate at a rate of 1 foot per second squared when a force of one pound is exerted on it. The video uses the slug to demonstrate how mass can be measured differently in the imperial system, stating that a person who weighs 161 pounds on Earth has a mass of 5 slugs.

💡SI Unit

The SI unit refers to the units of measurement defined by the International System of Units (SI). The video mentions that the SI unit for mass is the kilogram, highlighting the importance of standardized units for scientific measurements. It also contrasts this with the imperial system, which uses different units like the slug for mass and the pound for weight.

💡Balance

A balance is a device used to measure the mass of an object by comparing it to known masses. The video explains that mass is measured using a balance, which compares an unknown amount of matter to a known amount, thus determining the mass of the object. This is a fundamental method in laboratories and scientific settings to ascertain mass.

💡Matter

Matter is anything that has mass and occupies space. In the video, it is mentioned in the context of defining mass as 'the amount of matter an object contains.' The concept of matter is central to understanding mass, as it refers to the physical substance that constitutes an object, which can be atoms, molecules, or other particles.

💡Location

Location, in the context of the video, refers to the place or position of an object in space, which affects its weight due to varying gravitational forces. The video emphasizes that 'the mass of an object doesn't change when an object's location changes,' but weight does, as it is influenced by the strength of gravity at different locations, such as on Earth, the Moon, or Mars.

💡Moon

The Moon is used in the video as an example of a celestial body with a different gravitational pull compared to Earth. It illustrates how an object's weight can change when its location changes, stating that an object that weighs 200 pounds on Earth would weigh only 32 pounds on the Moon. This example helps to demonstrate the concept of weight variation due to location.

Highlights

Mass and weight are not the same thing.

Mass is the amount of matter an object contains.

Weight is the force of gravitational attraction an object feels towards another object.

Mass is measured using a balance, comparing known and unknown amounts of matter.

Weight is measured on a scale.

An object's mass does not change with location.

An object's weight changes with location due to different gravitational pulls.

The SI unit for mass is the kilogram.

The kilogram was originally defined based on the mass of one liter of water.

The imperial system uses the slug as the unit for mass.

Weight is technically measured in Newtons, a measure of force.

A Newton is defined as the acceleration of 1 kilogram at 1 meter per second squared.

An object with a mass of 1 kilogram has a weight of about 9.8 Newtons on Earth.

The imperial system uses pounds to measure weight, defined in terms of the kilogram.

Weight varies on the moon and other planets, but mass remains constant.

A cube with a mass of 90.91 kilograms weighs 200 pounds on Earth and 32 pounds on the moon.

On Mars, the same cube would weigh 76 pounds, but its mass remains 90.91 kilograms.

On Jupiter, the cube would weigh 468 pounds, still with the same mass of 90.91 kilograms.

In conclusion, mass measures the amount of matter, while weight measures the force of gravity.

The SI unit for weight is the Newton, with 1 kilogram having a weight of about 9.8 Newtons on Earth.