While air resistance has little impact on aerial skiers it is a significant factor used by ski jumpers to increase their jump distance.
The significant maths for ski jumpers is therefore X-section area.
Here is the jump at Pyeong Chang, 2018. Just imagine going down that at top speed!!!
A ski jumper is set to jump in Pyeongchang.
Casey Larson USA Pyeong chang 2018
Ski jumpers increase their speed going down the ramp by reducing their X-section area:
Lindsey Van, USA, practicing in a wind tunnel
Once they leave the ramp, ski jumpers try to increase their X-section area like Ski Divers to slow their vertical fall. But they have to land safely so they keep their skis at a minimum angle.
Abby Hughes, USA, practicing in a wind tunnel.
Abby Hughes, USA, in the air
Here are the X-section areas for Abby Hughes*:
Here is the formula for Air Resistance of Drag:
D = ½CApv2
Where C is the drag coefficient or constant, which depends on the shape and spin of an object. It is found by testing the object in a wind tunnel.
As Abby Hughes has tripled her X-section area in the air, she will have tripled the vertical drag during her jump. This will slow here decent.
*Mathspig calculated the X-section area by the old fashioned method of counting squares and rounding off the final count. Mathspig sized the two pics of Abby Huges so that her head was the same size in both pictures.
Here is the x-y graph for different launch angles.
trajectory wired magazine
You can go to this page for complete calculations. Aerial skiers twist and turn but their CENTRE OF GRAVITY must follow this graph. More on centre of Gravity at The Great Back Pack Attack ie.
The centre of gravity of Aerial Skiers must follow a
On April 12 2017 16-year-old Davis Cripe collapsed at school in South Carolina and died later in hospital.In the span of two hours, Davis drank a cafe latte from McDonald’s and a large Mountain Dew, then “chugged” a 16-ounce energy drink when he got back to art class.
Here, assuming Davis drank large sized drinks, is the lethal caffeine consumption.
NOTE: Davis lived in the USA where standard drink volumes are slightly different to Australia & UK. The USA volumes are used here converted to litre and ml.
The official cause of death was “caffeine-induced cardiac event causing a probable arrhythmia,” the coroner concluded. Source: Washington Post
Caffeine can kill.
WARNING: “Mixing caffeine with alcohol is a dangerous practice because it may lead to higher levels of alcohol consumption as the person often believes and feels they are more alert,” said Dr Robert Glatter, ER doctor at Lenox Hill Hospital, NYC . “The risk of alcohol poisoning increases as people consume more alcohol because they feel the caffeine will keep them awake and alert.” Source: USA Today
On April 12 2017 16-year-old Davis Cripe collapsed at school in South Carolina and died later in hospital.In the span of two hours, Davis drank a cafe latte from McDonald’s and a large Mountain Dew, then “chugged” a 16-ounce energy drink when he got back to art class.
Here, assuming Davis drank large sized drinks, is the lethal caffeine consumption.
NOTE: Davis lived in the USA where standard drink volumes are slightly different to Australia & UK. The USA volumes are used here converted to litre and ml.
The official cause of death was “caffeine-induced cardiac event causing a probable arrhythmia,” the coroner concluded. Source: Washington Post
Caffeine can kill.
WARNING: “Mixing caffeine with alcohol is a dangerous practice because it may lead to higher levels of alcohol consumption as the person often believes and feels they are more alert,” said Dr Robert Glatter, ER doctor at Lenox Hill Hospital, NYC . “The risk of alcohol poisoning increases as people consume more alcohol because they feel the caffeine will keep them awake and alert.” Source: USA Today
This is a vibration plate. Sand collects in the areas which do not vibrate and create patterns. The patterns are called CHLADNI figures.
In fact, the sand collects in places where standing waves – waves that cancel each other out – form. The rest of the plate is vibrating and making the sound.
You will find more info about this violin shaped vibration plate here.
The frequency of the sound creating this Chladni pattern is shown in Hertz Hz
Eddie Woo is an Aussie Maths teacher who runs his own Youtube Channel. So popular is this channel in October 2015, Woo won the NSW Premier’s Prize for Innovation in Science and Mathematics. This youtube clip won’t tell you where you will use surds, but it does something magical.
It compares surds to different kinds of music to help students understand why mathematicians go crazy over the concept of surds. This clip tells why maths is soooooo special. There is no guesswork or fake information in this maths. Maths must be accurate. And surds demonstrate this point. (Look for the 5 min mark)
Will you use surds in real life?
Maybe. Probably, not. But surds are used in mathematical programs that demand accuracy. eg. engineering skyscrapers, building satellite dishes, and even in video games. But you won’t see them. Like so much mathematics surds will be hidden in some algorithm.
Here are two Examples:
1. The Golden Ratio:
Often written a 1:1.61 the Golden Ratio or Fibonacci Sequence appears in art and nature and has an aesthetic appeal to the eye, but the accurate ratio is:
2. The Quadratic Function
Satellite dishes, headlights, torches, and bridges all designed using the parabolic arc. The parabola is defined by the quadratic function and sometimes solving for x produces an irrational no. namely a surd. Rounding off can introduce inaccuracies that can become more dramatic when scaled up to the sie of, say, a bridge.
Mathspig Blog 
