By Tanya Nguyen Period 1,2 11/21/11 Hayes – Physics Physics Project “Ballin’ On The Moon” By Tanya Nguyen Period 1,2 11/21/11 Hayes – Physics Physics Project

You are helping NASA engineers design a basketball court for a colony on the moon. How do you anticipate the ball’s motion compared with its motion on Earth? What changes will there be for the players— how they move and how they throw the ball? What changes would you recommend for the size of the court, the basket height, and other regulations in order to adapt the sport to the moon’s low gravity? Let’s find out!

Did you know that… The moon has less mass than Earth, therefore the force due to gravity on the moon’s surface is only about 1/6 of that on Earth. gEarth = 9.8 m/s2 gMoon = 1.6 m/s2

Wait, what?! So basically, we can throw almost up to 10 times further on the moon than on earth! So if we were to pass the basketball to another player on the team, we should not pass the ball in a high direction mainly because passing it higher up in the air will keep the projectile in the air longer due to the gravity on the moon. If we want to pass the ball quicker, we should pass it in a lower direction and more gently.

Gravity on the Moon Gravity on the moon is only 1/6 as much as Earth's. So if gravity on the moon is 1/6th of Earth, the range is 6 times as far. For example: If a basketball player jumps a horizontal distance of 5.0 m. on Earth, the player will jump 30.0 m. on the moon. Also, there is no air friction or air resistance on the moon.

How does it affect how they play? The basketball players motion would be slower on the moon than on Earth due to the gravity. If they play on earth, gravity would be holding them to the ground and on the courts but when played on the moon, there is no from of gravity. The game would be based on height when playing on the moon and the players would be able to jump in the air.

Also… The players would also be able to jump and reach the hoop and not miss. Also the shape of a jump shot is the same on the earth and the moon in the path of a parabola or a curve, the players would have no problem adjusting when shooting and the basketball would go in a path without air resistance. Their jumps horizontally would multiply by six times! They could also take shot from tremendously further out.

How high? All things are equal, a basketball player can jump roughly 6 times higher on the Moon than on Earth. So a three foot jump on Earth becomes an 18 foot jump on the Moon. To make a basketball court, the first thing you would need to do is raise the hoop or basket height from 10 ft to about 60 ft in order to make the game on the moon consistent with the gravity field there.

How Wide? The sizes of the basketball court should be wider primarily because on the moon, the range is 6 times as far so everything must be 6 times larger. A typical basketball court on Earth is 94x50 feet, so our Moon court would be 564 x 300ft. The rim height would have to be about 60 feet, instead of the usual 10. The three point arc would be about 130 feet out instead of the usual 22 ft.

How do the players adapt? Due to the lack of air on the Moon, each player would need their own breathing device or helmet in order to breathe while playing on the Moon. They would also need to wear a space suit to protect their bodies from the atmosphere of space.

What else is different? The launch velocity or the toss would be the same on the Moon as on the Earth, however the parabolic trajectory would be different on the Moon. The basketball would go higher to reach the max height and descend from there with 1/6 the acceleration we would have on Earth. Eye hand coordination, used to Earth's trajectories, would have to be retrained to get used to the Moon's extended trajectory.

In addition… Neglecting air resistance, a projectile has a constant horizontal velocity and constant downward free-fall acceleration. In the absence of air resistance, projectiles follow a parabolic path

What happens when you make a shot? Much less force would be required to make a shot on the Moon. If you shoot the ball up with the same initial velocity that you would on earth, it would go higher on the moon but slower as it isn't being pulled down as quickly. When it strikes the surface, it will do so at the same speed as what you shot it at, but it would take longer to reach that speed and travel farther.

Will it travel far? When dribbling the basketball on the court, the ball would bounce higher and fall more slowly on the moon. Throwing a ball on the moon would be exactly like throwing a ball on Earth, except that it would go much farther and slower because of the 1/6th gravity on the Moon and the lack of air resistance. Eventually, it would hit the ground. The Moon has no air resistance or air friction.

In Conclusion In order to make the appropriate basketball court for the moon… Use a lighter ball, so that the players can pass the ball down easier when dribbling . You wouldn't have to worry about the ball being too light since there is very little atmosphere on the moon, and therefore very little air resistance. Raise all of the basketball nets to account for the fact that the lower gravity would allow players to shoot the ball further and higher than usual (having a lighter ball would compound this, so the nets should be made very high). Extend the length of the courts.