Excellent Covid-19 stats update here.
If no preventative measures were taken by governments around the world then we could have been looking at a Plague Worse Case Scenario here.
Archive for the ‘algebra’ Category
DAY 60 Covid-19 .. some CURIOUS Stats
March 22, 2020
DAY 50 Covid-19 …. some STATS
March 13, 2020
Happy Valentine’s Day Graph
February 14, 2020The New York Times (The Perfect Valentine? A math formula 14 FEB 2019) has published an interactive widget from my favourite math website IMAGINARY for Valentine’s Day.
Here is the formula:
You’ll find IMAGINARY’S interactive LOVE widget HERE.
2. Stuntman Math: Jumping off a Building
October 14, 2019This is a repost of Mathspig’s very popular Stuntman/woman series.
The main concern when jumping off a building is that the airbag (cardboard boxes) cover the drop zone.
The maths calculations involved in jumping off a building are straightforward. You might like to check out How Maths Solved a real murder.
Jump Height that Kills
It doesn’t take much of a fall to cause damage. Sean Hughes, professor of surgery at Imperial College, London. Says “From a height of 3m you could fracture your spine,” he says. “At around 10m, you’re looking at very serious injuries.” (The Guardian, 20 MAY 2014)
Stunt Jump from building from standing start
As this jump – as in most base jumps – involves a standing start:
Stunt jump from building running
We will assume you are no Usain Bolt. His running speed, the fastest in the world, is 44.72 km/h (12.42m/s, 27.44 mph).
We’ll say your running speed on take-off is:
Vy = 15 mph = 24.1 kph = 6.7 m/sec
Don’t do this at home.
NB: Airbag dimensions: 20m x 20m x 4 m
Handstand of death
Would you jump off a 25 story building?
3. STUNTMAN MATH: Motorbike Jump
October 9, 2019This is a repost of Mathspig’s very popular Stuntman/woman series.
Star Stuntmen
Star Stuntmen Monte Perin (pictured) has involved many films, including “Spider-Man,” “Star Trek, “Indiana Jones and the Kingdom of the Crystal Skull” and portraying Arnold Schwarzenegger’s stunt double in “Terminator 3: Rise of the Machines.”
Perhaps his most difficult stunt was landing his Harley in an open boxcar of a moving train for Disney’s 2008 Adam Sandler movie “Bedtime Stories”. In a career of over 25 years Perin has broken “almost everything” including both his arms, legs, knees, feet, ankles, several ribs, his back and his pelvis. See Confessions of a stuntman
Veteran stuntman Evel Knievel (1938 – 2007) was the pioneer of many stunt jumps. Here he is jumping 10 cars and 3 vans in 1973.
His injuries are legendary:
More Evel Knievel
Ramp Design
The angle of the kicker in ramp design can vary from 100 – 700 (See below)
Moto-X Ramp Jump Maths
As any bike nut knows increasing speed and angle of take off will increase jump distance.
Here is a graph from final gear for speed vs angle to jump 90m.
METHOD 1 is approximate (See STEP 1 & STEP 2 above), but as METHOD 2 produces the same ans (See above), it is very useful.
You will find a thoroughly detailed calc for STUNT JUMP MATHS here:
And everything you ever wanted to know about PHYSICS OF STUNT JUMPS here.
Why do so many students HATE MATH? … um, you know, BOREDOM
September 28, 2019According to ‘Bored Out of Their Minds’, an article by ZACHARY JASON in The Harvard Ed Magazine (2017):
Boredom accounts for nearly a third of the variation in student achievement.
Half of high school dropouts cite boredom as their primary motivator for leaving.
Boredom begins for Math students at Grade 6 when students (Common Core Standards, USA) tackle more abstract concepts such as linear eqns, exponents, probability, geometry and so on.
Math curriculums in the USA, UK & Australia all demand students solve REAL LIFE problems. Too often these are of the type:
Q. Ronaldo has tethered his goat on a 12ft rein in the corner of a 20ft square field. What area can the goat graze?
THE ANS: Who cares?
Simple.
Ask students maths questions which have answers they want to know.
Students really don’t care about Ronaldo’s goat, but here are some questions which involve intriguing answers they might want to work out. And many of these questions involve funny or age-relevant activities, which also helps engagement.
1. Mean, Median STATS: Mean, Median and Coffee: Busting an Urban Myth
2. Parabolas: Can you beat the 12-14 yo World Record for a Watermelon Pip spit?
3. Geometry: Build a Freestanding Tower
Rates (Speed) & Units:
4a. The Terrifying Math of Running from a bear
5. Decimals, %, Volume: What Volume of alcohol is lethal for teens?
6. Decimals, Algebra, Weight Units
How much blood can a kid lose and survive?
Graph Hunger Game Math
7. GEOMETRY. Angles
Any Topic:
8. Middle School Math Photo Scavenger Hunt
Space Math Song here
EVEN TEACHERS GET BORED!!!
The average time it takes an audience at a conference to switch off is 11 minutes. Keep in mind this audience is, at least, being paid to be bored witless.
Can you escape a FALLING TREE?
August 24, 2019
Tragically, 5 people have been killed by falling trees in Victoria, Australia, this Winter.
In 3 separate accidents, 4 died when trees crushed the occupants in cars. One victim was a pedestrian.
So if you were walking through a park could you escape a falling tree if you either heard a cracking sound or saw the tree starting to fall?
With thanks to Physics Stack Exchange.
For an inverted pendulum near the top of its arc, there is no period, but the quantity √ℎ/𝑔 does represent a characteristic time scale for this system. The tree will take a few of these characteristic times to fall.
Mathspig hates seeing an old tree felled, but it does give us the necessary time data.
There are many assumptions in these calculations.
*You’d be hit by the tree trunk, not a branch which would hit you sooner.
*There is no wind pushing the tree over.
*The tree falling is an approx to a reverse pendulum.
