Backspin Basketball Flies Off Dam

VeritasiumHow RidiculousphysicsMagnus effectaerodynamicsGordon Dambasketball trick shotscience experimentFlettner rotorfluid dynamics

This video from Veritasium explains the Magnus effect, a physical phenomenon that affects rotating objects moving through a fluid. The demonstration begins at the Gordon Dam in Tasmania, where a basketball dropped with backspin curves dramatically, unlike one dropped without spin. The video then uses animations to explain the aerodynamics of how the spin creates a pressure differential, resulting in a sideways force. It covers the history of the effect's discovery, its applications in sports like tennis and soccer, and its experimental use in engineering, such as Flettner rotor ships and rotor-wing aircraft.

Transcription

Recently, some friends of mine went to the Gordon Dam in Tasmania, which is 126 and a half meters or 415 feet high. Then they dropped a basketball over the edge. You can see that the basketball gets pushed around a bit by the breeze, but it lands basically right below where it was dropped. Now watch what happens when they drop another basketball, but this time with a bit of backspin. Oh, look at that go! That's incredible. So you want us to get back in the water, do you? This is Brett who just threw it. I literally just dropped it with a bit of spin, like I didn't even throw it, and it just took off. Like, we had no idea that was gonna do that. And this is where I come in. The basketball was subject to the Magnus effect, which affects all rotating balls or cylinders as they fly through the air. And it works like this. As the basketball picks up speed, air on the front side of the ball is going in the same direction as its spin, and therefore it gets dragged along with the ball and deflected back. Air on the other side is moving opposite to the ball's spin, so the flow separates from the ball instead of getting deflected. The net result is the ball pushes air one way, so the air applies an equal force on the ball the other way. And this is known as the Magnus effect, named after Heinrich Gustav Magnus who described it in 1852. Of course, Isaac Newton beat him to it by nearly 200 years, describing the flight of tennis balls at Cambridge College. But, you know, he's got enough stuff named after him. This effect is very important in sports like tennis, soccer, and golf. But could it have non-sport applications? Perhaps. This is a sailboat. I know it doesn't look like a sailboat, but those aren't chimneys. They are spinning cylinders called Flettner rotors, and they take the place of the sails. They deflect crosswinds using the Magnus effect to propel the ship forwards. And this is a plane with spinning cylinders instead of wings. Using the Magnus effect, the cylinders actually generate more lift than traditional wings. However, they also generate way more drag, making them impractical. This plane only flew once, and then it crashed. But the Magnus effect is making a comeback. Here is an experimental rotor wing aircraft, which generates all its lift from spinning cylinders. And this is the E-Ship 1, which uses four spinning cylinders, that's four Flettner rotors, to increase its efficiency and reduce the amount of diesel it burns. So in the future, the Magnus effect may help more than just basketballs fly. Oh, look at that go! That's incredible. Now the real reason my friends from How Ridiculous were at the dam was to set the world record for the highest basket ever scored. So go check out their channel and the video and subscribe to them for more epic trick shots.

Visual Timeline

0:02
wide shot high-angle adventurous

A group of people walks up a steep concrete ramp alongside a massive concrete dam wall.

"Recently, some friends of mine went to the Gordon Dam in Tasmania,"

Setting: Gordon Dam, Tasmania, Australia — bright, natural daylight with strong shadows

People (2):

• walking up a ramp, wearing light blue short-sleeve shirt and khaki pants, short brown hair — not visible

• walking up a ramp, wearing dark jacket and dark pants, short dark hair — not visible

Colors:concrete gray, dark brown, khaki, light blue, dark green
0:06
extreme wide shot overhead, looking straight down awe-inspiring

A camera pans down the immense, curved face of the concrete dam.

"which is 126 and a half meters or 415 feet high."

Setting: Gordon Dam, Tasmania — bright, natural daylight

basketball hoop (white)

Text: "126.5 m (415 f"

Colors:concrete gray, rust orange, dark brown, white, light blue
0:13
medium shot first-person point-of-view, looking down anticipatory

From a first-person perspective, a person's hands hold an orange basketball over the edge of the dam, then release it.

"Then they dropped a basketball over the edge."

Setting: Gordon Dam, Tasmania — overcast daylight

People (1):

• leaning over a railing, wearing black jacket — not visible

basketball (orange)
Colors:orange, dark green, gray, flesh tone, dark blue
0:17
wide shot overhead, looking straight down observational

The camera follows the orange basketball as it falls straight down towards the gravel-covered ground at the base of the dam.

"You can see that the basketball gets pushed around a bit by the breeze, but it lands basically right below where it was dropped."

Setting: Gordon Dam, Tasmania — overcast daylight

basketball (orange)
Colors:gray, green, orange, dark gray, brown
0:23
medium shot first-person point-of-view, looking down experimental

From a first-person perspective, a person's hands hold a basketball, give it a slight backward spin, and drop it over the edge of the dam.

"Now watch what happens when they drop another basketball, but this time with a bit of backspin."

Setting: Gordon Dam, Tasmania — overcast daylight

People (1):

• leaning over a railing, wearing black jacket — not visible

basketball (orange)
Colors:orange, dark green, gray, flesh tone, dark blue
0:28
wide shot overhead, looking down surprised, amazed

The camera follows the spinning basketball as it falls and curves dramatically away from the dam wall, flying horizontally over the canyon.

"Oh, look at that go!"

Setting: Gordon Dam, Tasmania — overcast daylight

basketball (orange)
Colors:dark blue, dark green, gray, orange, brown
0:37
medium shot eye-level amused, lighthearted

A young man in a black and yellow jacket smiles and laughs while leaning on the railing at the top of the dam.

"So you want us to get back in the water, do you?"

Setting: Gordon Dam, Tasmania — overcast daylight

People (1):

• standing, leaning on a railing, wearing black and yellow waterproof jacket, short brown hair — smiling, looking towards the camera

walkie-talkie (black)

Text: "So you want us to get back in the water, do you?"

Colors:black, gray, yellow, green, flesh tone
0:44
wide shot overhead, looking down recollective, amazed

A replay of the basketball with backspin being dropped and curving away from the dam.

"I literally just dropped it with a bit of spin, like I didn't even throw it, and it just took off. Like, we had no idea that was gonna do that."

Setting: Gordon Dam, Tasmania — overcast daylight

basketball (orange)
Colors:dark blue, dark green, gray, orange, brown
0:52
wide shot eye-level educational, introductory

A man walks into frame from the left on a large, dry dirt field in front of old brick university buildings.

"The basketball was subject to the Magnus effect, which affects all rotating balls or cylinders as they fly through the air."

Setting: University campus quad — bright, sunny day

People (1):

• walking, wearing dark sweater over a collared shirt and dark pants, balding hair — neutral expression

flagpole (white)

Text: "THE MAGNUS EFFECT"

Colors:light brown, green, dark brown, gray, light blue
0:59
medium shot eye-level explanatory, scientific

An animated red basketball appears against a black background. White vertical lines representing airflow move downwards past the ball.

"And it works like this. As the basketball picks up speed, air on the front side of the ball is going in the same direction as its spin,"

Setting: animated graphic — artificial, focused on the animation

animated basketball (red)
Colors:black, red, white, dark red
1:45
medium shot eye-level illustrative

The animated basketball is shown spinning. The airflow lines on the left side (direction of spin) are shown clinging to the ball and being deflected to the right.

"and therefore it gets dragged along with the ball and deflected back."

Setting: animated graphic — artificial, focused on the animation

animated basketball (red)

Text: "->"

Colors:black, red, white, gray
1:50
medium shot eye-level explanatory

The animation now focuses on the right side of the spinning ball, where the airflow lines separate from the surface and continue downwards.

"Air on the other side is moving opposite to the ball's spin, so the flow separates from the ball instead of getting deflected."

Setting: animated graphic — artificial, focused on the animation

animated basketball (red)
Colors:black, red, white, gray
1:57
medium shot eye-level conclusive, scientific

Two large white arrows appear on the animation. One points right, away from the deflected air. The other points left, indicating the force on the basketball.

"The net result is the ball pushes air one way, so the air applies an equal force on the ball the other way."

Setting: animated graphic — artificial, focused on the animation

animated basketball (red)

Text: "->", "<-"

Colors:black, red, white, gray
2:04
close-up eye-level historical

A black and white portrait of Heinrich Gustav Magnus is shown.

"And this is known as the Magnus effect, named after Heinrich Gustav Magnus who described it in 1852."

Setting: photograph — soft, directional studio lighting

People (1):

• seated for a portrait, wearing dark formal jacket, white high-collar shirt, dark, wavy, receding hairline hair — serious, direct gaze

Colors:black, white, gray, sepia
2:09
close-up eye-level historical, informative

A painted portrait of Isaac Newton is shown.

"Of course, Isaac Newton beat him to it by nearly 200 years, describing the flight of tennis balls at Cambridge College."

Setting: oil painting — dramatic, chiaroscuro-style lighting

People (1):

• seated for a portrait, wearing dark red or brown coat, long, gray, curly wig hair — pensive, looking slightly to the right

Colors:dark brown, white, flesh tone, reddish-brown, gray
2:19
medium shot low-angle, behind the player dynamic, athletic

A soccer player kicks a ball, which curves through the air and into the goal.

"This effect is very important in sports like tennis, soccer, and golf."

Setting: soccer field — bright, natural daylight

People (1):

• kicking a soccer ball, wearing white t-shirt, blue socks and white shorts, short dark hair — not visible

soccer ball (white and black)soccer goal (white)
Colors:green, white, blue, black, brown
2:25
wide shot eye-level curious, historical

A black and white archival photograph of the Flettner-Rotor ship 'Buckau' is shown on the water.

"This is a sailboat. I know it doesn't look like a sailboat, but those aren't chimneys."

Setting: at sea — overcast daylight

Flettner-Rotor ship (black and white)

Text: "FLETTNER-ROTOR"

Colors:black, white, light gray, dark gray
2:36
close-up on the animation overhead educational, technical

An animated diagram shows a top-down view of a ship with two spinning rotors. Lines representing wind flow from the right, are deflected by the rotors, and arrows show the resulting forward thrust on the ship.

"They deflect crosswinds using the Magnus effect to propel the ship forwards."

Setting: animated graphic — artificial

animated ship (gray)

Text: "This force is called the Magnus Force."

Colors:dark blue, white, gray, light blue, green
3:25
medium shot straight-on historical, intriguing

A black and white newspaper clipping from 'Popular Science Monthly' is shown, with the headline 'Whirling Spools Lift This Plane'.

"Using the Magnus effect, the cylinders actually generate more lift than traditional wings."

Setting: archival document — even, flat lighting

newspaper page (off-white)

Text: "Whirling Spools Lift This Plane"

Colors:off-white, black, gray
3:38
medium shot eye-level, from behind innovative, hopeful

A man in a white cap launches a small, experimental aircraft with a large, colorful spinning cylinder for a wing. The aircraft flies away over a hilly, wooded landscape.

"But the Magnus effect is making a comeback. Here is an experimental rotor wing aircraft, which generates all its lift from spinning cylinders."

Setting: outdoor, rural area — overcast daylight

People (1):

• standing, watching the aircraft, wearing dark jacket, gray/white hair — not visible

rotor wing aircraft (multi-colored)
Colors:light blue, green, brown, white, red
3:46
wide shot high-angle, aerial modern, industrial

An aerial shot shows a large, modern green cargo ship (the E-Ship 1) with four tall, white Flettner rotors, moving through the water.

"And this is the E-Ship 1, which uses four spinning cylinders, that's four Flettner rotors,"

Setting: at sea — bright, slightly overcast daylight

E-Ship 1 cargo ship (green and white)
Colors:grayish-blue, green, white, red, dark gray
3:55
wide shot first-person point-of-view, looking down conclusive, awe-inspiring

A replay of the basketball being dropped with backspin from the dam, showing its dramatic, curving flight path away from the camera.

"So in the future, the Magnus effect may help more than just basketballs fly."

Setting: Gordon Dam, Tasmania — overcast daylight

People (1):

• leaning over a railing

basketball (orange)
Colors:dark green, gray, orange, dark blue, flesh tone
4:04
full screen graphic straight-on promotional

An end screen appears with four quadrants. The top two are subscribe links for 'Veritasium' and 'How Ridiculous'. The bottom two show clips from other videos.

Setting: end screen — graphic

Text: "Click here to subscribe", "Veritasium", "Click here to subscribe", "HOW RIDICULOUS"

Colors:black, white, blue, red, orange
4:11
wide shot high-angle, looking down exciting, triumphant

A clip from the 'How Ridiculous' video shows the basketball falling from a great height and going through the hoop at the base of the dam.

"Now the real reason my friends from How Ridiculous were at the dam was to set the world record for the highest basket ever scored."

Setting: Gordon Dam, Tasmania — overcast daylight

basketball (orange)basketball hoop (black and white)
Colors:gray, green, orange, black, white
4:16
medium shot eye-level jubilant, celebratory

A group of men on top of the dam celebrate wildly, hugging, raising their arms, and cheering after making the record-breaking shot.

"So go check out their channel and the video and subscribe to them for more epic trick shots."

Setting: Gordon Dam, Tasmania — bright daylight

People (2):

• hugging and celebrating, wearing red jacket, short brown hair — cheering, ecstatic

• celebrating with others, wearing blue jacket, short brown hair — yelling in excitement

Colors:gray, red, blue, green, flesh tone