Uploaded August 2026 | Updated September 2026, 3 weeks ago
#ngsciencex #ngscience #Gravity #Physics #apollo15
Do heavier objects fall faster than lighter objects? It certainly looks that way on Earth. Drop a hammer and a feather from the same height and the hammer will reach the ground first. But this everyday observation does not tell us the whole story.
The reason is air resistance.
As objects fall through Earth’s atmosphere, they collide with air molecules. This creates a force called drag, or air resistance, which acts against their motion. A light object with a large surface area, such as a feather, is affected much more strongly by air resistance than a dense, compact object such as a hammer.
Remove the air, however, and something remarkable happens.
In a vacuum, objects fall with the same gravitational acceleration regardless of their mass. A heavy object does not fall faster simply because it weighs more.
One of the most famous demonstrations of this principle took place during NASA’s Apollo 15 mission to the Moon in 1971.
Apollo 15 commander David Scott stood on the lunar surface holding a geological hammer in one hand and a feather in the other. The feather was a falcon feather, chosen in reference to the Apollo 15 lunar module, Falcon.
Scott released the hammer and feather at approximately the same time.
On Earth, we would expect the hammer to quickly leave the feather behind. But the Moon has virtually no atmosphere, so there was almost no air resistance acting on either object.
The hammer and feather fell together and struck the lunar surface at essentially the same time.
It was a dramatic demonstration of one of the fundamental ideas of physics: in the absence of air resistance, gravitational acceleration does not depend on the mass of the falling object.
Near Earth’s surface, objects undergoing free fall accelerate at approximately 9.8 metres per second squared (9.8 m/s²). This means that, ignoring air resistance, their downward velocity increases by about 9.8 metres per second every second.
Gravity pulls more strongly on a more massive object, but that object also has greater inertia — greater resistance to a change in its motion. These effects balance, producing the same gravitational acceleration.
The Moon’s gravity is weaker than Earth’s, with a gravitational acceleration of approximately 1.62 m/s², so objects fall more slowly there. But the same principle applies: without significant air resistance, objects of different masses accelerate together.
This idea is closely associated with the development of our modern understanding of motion and gravity. Experiments and mathematical reasoning helped overturn the ancient belief that heavier objects must naturally fall faster than lighter ones.
The Apollo 15 hammer-and-feather experiment provided an unforgettable demonstration in an environment that scientists on Earth normally have to reproduce using a vacuum chamber.
So, do heavier objects fall faster?
On Earth, they sometimes appear to because air resistance affects different objects differently. In a vacuum, however, objects fall with the same gravitational acceleration regardless of mass.
Myth? BUSTED.
NGScienceX brings science concepts to life through clear explanations, animations, experiments, real-world examples and extraordinary moments from scientific history.
Explore more videos about gravity, forces, motion, acceleration, free fall, air resistance, Newton’s laws, space science, the Moon, NASA, Apollo missions and physics experiments with NGScience and NGScienceX.
Perfect for students, teachers, homeschoolers and anyone curious about how the universe works.
Topics covered in this video:
gravity, gravitational acceleration, free fall, air resistance, drag, mass, weight, forces, motion, acceleration, vacuum, Moon gravity, Apollo 15, David Scott, hammer and feather experiment, NASA Moon landing, lunar science, physics experiments, falling objects, Galileo, Newtonian physics, science education, secondary science, middle school science, high school physics, STEM education.
#ngsciencex #ngscience #Gravity #Physics #apollo15
Do heavier objects fall faster than lighter objects? It certainly looks that way on Earth. Drop a hammer and a feather from the same height and the hammer will reach the ground first. But this everyday observation does not tell us the whole story.
The reason is air resistance.
As objects fall through Earth’s atmosphere, they collide with air molecules. This creates a force called drag, or air resistance, which acts against their motion. A light object with a large surface area, such as a feather, is affected much more strongly by air resistance than a dense, compact object such as a hammer.
Remove the air, however, and something remarkable happens.
In a vacuum, objects fall with the same gravitational acceleration regardless of their mass. A heavy object does not fall faster simply because it weighs more.
One of the most famous demonstrations of this principle took place during NASA’s Apollo 15 mission to the Moon in 1971.
Apollo 15 commander David Scott stood on the lunar surface holding a geological hammer in one hand and a feather in the other. The feather was a falcon feather, chosen in reference to the Apollo 15 lunar module, Falcon.
Scott released the hammer and feather at approximately the same time.
On Earth, we would expect the hammer to quickly leave the feather behind. But the Moon has virtually no atmosphere, so there was almost no air resistance acting on either object.
The hammer and feather fell together and struck the lunar surface at essentially the same time.
It was a dramatic demonstration of one of the fundamental ideas of physics: in the absence of air resistance, gravitational acceleration does not depend on the mass of the falling object.
Near Earth’s surface, objects undergoing free fall accelerate at approximately 9.8 metres per second squared (9.8 m/s²). This means that, ignoring air resistance, their downward velocity increases by about 9.8 metres per second every second.
Gravity pulls more strongly on a more massive object, but that object also has greater inertia — greater resistance to a change in its motion. These effects balance, producing the same gravitational acceleration.
The Moon’s gravity is weaker than Earth’s, with a gravitational acceleration of approximately 1.62 m/s², so objects fall more slowly there. But the same principle applies: without significant air resistance, objects of different masses accelerate together.
This idea is closely associated with the development of our modern understanding of motion and gravity. Experiments and mathematical reasoning helped overturn the ancient belief that heavier objects must naturally fall faster than lighter ones.
The Apollo 15 hammer-and-feather experiment provided an unforgettable demonstration in an environment that scientists on Earth normally have to reproduce using a vacuum chamber.
So, do heavier objects fall faster?
On Earth, they sometimes appear to because air resistance affects different objects differently. In a vacuum, however, objects fall with the same gravitational acceleration regardless of mass.
Myth? BUSTED.
NGScienceX brings science concepts to life through clear explanations, animations, experiments, real-world examples and extraordinary moments from scientific history.
Explore more videos about gravity, forces, motion, acceleration, free fall, air resistance, Newton’s laws, space science, the Moon, NASA, Apollo missions and physics experiments with NGScience and NGScienceX.
Perfect for students, teachers, homeschoolers and anyone curious about how the universe works.
Topics covered in this video:
gravity, gravitational acceleration, free fall, air resistance, drag, mass, weight, forces, motion, acceleration, vacuum, Moon gravity, Apollo 15, David Scott, hammer and feather experiment, NASA Moon landing, lunar science, physics experiments, falling objects, Galileo, Newtonian physics, science education, secondary science, middle school science, high school physics, STEM education.
