Archive for the ‘Rates’ Category

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Razzle-Dazzle them with Middle School Math that is, like, WOW!

September 4, 2022

 

10 Quick & Quirky Ways to Make the Math Classroom Rock!

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1. Tell a Story: Life, Death, and Geometry

This is middle school maths at its best. To understand Wild Fires you must understand the angle of a slope. REQUIREMENTS: Just this story and a white or blackboard to show how the fire speed changes with the slope angle. 

Background Story

On 5th August 1949 Wag Dodge was dropped by parachute with 14 other firefighters into Mann Gulch, a steep-sided gully in a Montana pine forest. Firefighters who parachute in to put out small blazes started by lightning are called Smoke Jumpers. As they worked their way down the sides of the gully the breeze was blowing away from them. But the wind soon shifted. This produced an updraft, which increases the speed of the fire front. The 15 Smoke Jumpers turned and started running for their lives uphill.

What you have to know

Heat rises and so there is a Chimney Effect pushing the fire uphill. The rule of thumb used by firefighters is:

Each 10º increase in slope, the fire front speed doubles. So a fire front traveling at 60 kph (37 mph) becomes a fire front traveling at 120kph (75 mph) moving up a slope of 10º.

What happened to the Smoke Jumpers?

When the fire front changed direction Wag Dodge and 14 other Smoke Jumpers found themselves running for their lives up a steep slope. What did Wag do next?

ANS: Here’s the amazing thing. Wag realised he could not outrun the fire at that point. So he stopped, took off his backpack, took out some MATCHES, and lit a fire in the grassy patch in front of him. Just before the firewall hit he threw himself face down on the burnt patch. He survived. The other 14 firefighters did not. You will find maths exercises here: METRIC UNITS and USA UNITS.

 

Requirements: SmartBoard to Project this link.

Try it first. You might be surprised.

 

3. Urban Myth Busted

Requirements: This story.

Goldfish Memory This is what Epidemiologists do. They find out if there are statistics to support the theory. These mathematicians have been providing vital information during the COVID-19 Pandemic.

According to the ABC news, this myth was busted by a 15-year-old Adelaide schoolboy named Rory Stokes. He fed his goldfish near a Red Lego brick. The fish started anticipating food near the brick. He took it away and replaced it several weeks later. The fish remembered the red brick!!! More here.

Other maths myths to check out:

Chewing food 32 times before swallowing helps you lose weight. Here.

You must drink 8 glasses of water a day. Here.

You are 6 degrees of separation from anyone in the world. Here.

It takes 43 muscles to frown and only 17 to smile. Here.

 

4. Beat this! Drum Rates in BPM.

Requirements: A pencil and a timer on a phone.

Can students manage a drumbeat to popular songs? Here are some songs with their BPMs (Beats per minute listed). 

Tones and I     Dance Monkey  98 BPM.

The Rubens  Live In Life  104 BPM.

Lady Gaga      Bad Romance     118  BPM

……………….Just Dance          119   BPM

Flume   Rushing Back   176  BPM   (Try the middle of the track. It varies)

Panic! At the Disco      186 BPM   (Recommended by Jog.FM for jogging)

More DRUM BEATS and a story about Drummers’ Brains here.

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5...MatHoudini

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Requirements: Phonebook.

Read the instructions at this link. Very simple. And you can amaze the students. Or Vice Versa. A student can amaze a maths teacher.

 

6.  Can you make a Square Bubble?

Requirements: pipe cleaners or stick cube and detergent and a bucket with water.

All ages love this exercise.

How? Read the link here.

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7. Photo Scavenger Hunt

Challenge: Students use a smartphone to take 5 mathsy photos for homework. Ideas here.

However, start in the maths room. Look for parallel lines, angles, rectangles, spheres, parabolas (not in the textbooks). See parabola below.

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8. Barcode Maths

Requirements: A product with a barcode.

Read this link and check the barcode.

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9. Secret Code

Requirements: Box of matches, an accomplice.

Read this link and amaze the class.

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10. Rolling coin Paradox & the Radius 

Requirements: 2 large coins. 20c in Australia, Half-$ USA or 25p UK.

Read this link first. It’s so counterintuitive.

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Amazing and Terrifying Wildfire Maths . . . . . . . . . . . . . . METRIC UNITS

July 25, 2022

mathspig-smoke-jumpers  With wildfires  burning across the US and Europe , Mathspig had to update this firefighter maths post for middle school classrooms.

Radiant Heat Stats WA Fire Dept FACEBOOK, Australian Bushfires 14 NOV 2019 MyFireWatch WA

 Wildfires USA 2022 Map: NASA

mathspig-metric-units-fire-math

METRIC UNITS

Background Story

On 5th August 1949 Wag Dodge was dropped by parachute with 14 other fire fighters into Mann Gulch, a steep-sided gully in a Montana pine forest. Fire fighters who parachute in to put out small blazes started by lightening are called Smoke Jumpers. As they worked their way down the sides of the gully the breeze was blowing away from them. But the wind soon shifted. This produced an updraft, which increases the speed of the fire front. The 15 Smoke Jumpers turned and started running for their lives uphill.

HOW FAST CAN YOU RUN?

METRIC UNITS

Time Trial:

Mark out a 10 m course. Make 3 time trials.

t1 =

t2 =

t3=

Average your time:

tav = (t1 + t2 + t3)/ 3 =

Your Speed S = 10/tav = ……… m/sec

mathspig-firefirghter-maths-1

HOW FAST IS A GRASS FIRE?

This will, of course, vary depending on the wind speed. A typical grass fire in Australia in a flat area can travel at 20kph (up to 30 kph) in a gentle breeze.

Fire Front Speed Grass Fire

Fire Front Speed = 20 kph = 20 x1000/(60 x 60)

                               = 20 x 0.27777777 = 20 x 0.28 m/sec

                               = 5.6 m/sec

mathspig-firefighter-maths-2

CAN YOU OUT RUN A FIRE?

Average Running Speed Boy 13–14 yo = 3.0 m/sec

Average Running Speed Girl 13–14 yo = 2.4 m/sec

We’ll assume, boy or girl, that you are really motivated and can run away from the fire at top speed of 3.0 m/sec. Now calculate the distance you can run and the fire front moves in 10 secs intervals up to 1 minute.

mathspig-fire-fighter-table-1

This is not looking good. See more Firefighters Need Maths here.

We can do very accurate calculations using simultaneous equations. Wildfire Algebra: Detailed Worksheet using simultaneous equations and solutions  here.

NOW YOU ARE RUNNING UP HILL. WHAT HAPPENS?

We’ll assume, due to being motivated by having a fire licking your heels, that you can run at your top speed up hill for a short time, at least. But here is the problem.

Heat rises and so there is a Chimney Effect pushing the fire uphill. The rule of thumb used by fire fighters is:

Each 10º increase in slope, the fire front speed doubles.

mathspig-cfa-diag

mathspig-fire-fighter-table-2

Now you can calculate the distance travelled by the fire front up a slope at a 30º angle.

Don’t forget you can use the WEB 2.0 Calculator here.

mathspig-fire-fighter-table-3

Even at your top running speed, which is unlikely up a slope, you can run 180 m in 1 minute. In that time the forefront has moved 2688 m or 2.7 km.

It depends how far away you are from the fire front, but it seems you cannot out run this fire front.

Again we can do very accurate calculations using simultaneous equations.

See Firefighters Need Maths here.

Wildfire Algebra: Worksheet and solutions here.

CAN YOU OUT RUN A WILD FIRE?

High winds can turn a bush or forrest fire into a WILD FIRE with wind speeds up to 110 kph and temperatures up to 2000 °C, which can and does melt glass and cars.

The fire front speed doubles with every 10º, so speeds for the fire front can reach 220 kph, 330kph and up to 550kph.

20o-angle-mathspig-2

What happened to the Smoke Jumpers?

When the fire front changed direction Wag Dodge and 14 other Smoke Jumpers found themselves running for their lives up a steep slope. What did Wag do next?

ANS: Here’s the amazing thing. Wag realised he could not out run the fire at that point. So he stopped. Took off his back pack. Took out some MATCHES and lit a fire in the grassy patch in front of him. Just before the firewall hit he threw himself face down on the burnt patch. He survived. The other 14 firefighters did not.

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Dave Grohl and The Curious Nature of Drummers’ Brains

March 4, 2022

Live music is back.

The Foo Fighters play a stadium concert in Geelong TONIGHT. This is the first stadium concert in Australia in 2 years!!!!! Dave Grohl, the FF’s guitarist,  is a legend. He played drums for Nirvana and is considered by many to be the best drummer in the world. Meanwhile, Taylor Hawkins, the drummer for the Foo Fighters, is also considered one of the best rock drummers ever. 

In honour of this auspicious occasion and to work out what might be going on inside these rock legends’ heads, I’m reposting (below) the math article about drummers’ brains.

 

 

In a 2011 article in the New Yorker Burkhard Bilger wrote about neuroscientist David Eagleman and his research into time and the brain especially drummers’ brains.

Eagleman New Yorker

Some of the drummers he has interviewed and/or tested include William Champion of Cold Play, Brian Eno of Roxy Music and Larry Mullen, Jnr of U2.Roxy Music with Brian Eno

Eno, on keyboards (above) who was working on a U2 album,  talks about Mullen’s amazing timing.  They were using a click-track (computer generated beat) when mMullen complained he couldn’t drum to it. ENO adjusted the beat. Mullen was happy.

larry Mullen

ENO adjusted the beat by 6 milliseconds!!!!!!!!!

6 thousandths of a second or 0.006sec.

Cool Larry Mullen Jnr Drum solo

Tempo is measured in beats per minute or bpm. 

Drum Beats for different tracks:

Drum Beats

Here are some drum beats provided by Justin Alan Cox so you can get your timing right:

60 bpm

80 bpm

100 bpm

120 bpm

Drummer Maths:

How Cool a Drummer are you?

Pick a beat and see how accurate you can beat tempo. Time how long it takes you to beat out 60, 80, 100 or 120 drum beats using a pencil.  It should, obviously, take one minute if you are an ENO or a Mullens.

What was the difference in time in seconds?

But drummers like Eno, Grohl and Hawkins have other problems!!!!!

Bilger’s conclusion:

‘Like perfect pitch, which dooms the possessor to hear every false note and flat car horn, perfect timing may just makes a drummer more sensitive to the world’s arrhythmias and repeated patterns, Eagleman said—to the flicker of computer screens and fluorescent lights. Reality, stripped of an extra beat in which the brain orchestrates its signals, isn’t necessarily a livelier place. It’s just filled with badly dubbed television shows.’

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22 Amazing Numbers for 2022

January 6, 2022

Answers Q 1 – 5 Here

Answers  Q 6 – 10 Here

Answers Q 11 – 16 Here


Answers Q 17 – 22 Here

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Braindead Math for Halloween

October 13, 2021

Tarantino, being a connoisseur of Fake Blood, used several types of Fake Blood in the film Kill Bill II ranging from good splatter to free-flowing blood. According to one fanzine, in this film, Uma Thurman killed 88 opponents with a sword.  So the numbers(above)are in the right ‘blood-soaked’ ballpark. More survival math (The Hunger Games) here.

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The Bitter Truth: How We See the Numbers

October 10, 2021

The pandemic has launched a data storm. But some numbers cut through this white out. Despite following the numbers closely I was shocked by the following headline on the front on The Washington Post a few weeks ago. 

Using data from the Worldometer Website, I thought it would be interesting see how other countries compare with the USA. America has already dropped below this grim marker. And low is not the way to go!!!!

NUMBER OF DEATHS IN COVID PANDEMIC

FIRST WORLD COUNTRIES

WORST: Peru                          1: 170   

BEST: New Zealand              1: 200,000  

Here are some more stats:

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Sound Math 2: Can you hear this high pitch sound?

September 30, 2021

One of the best summaries of sound can be found here at Maths is Fun

Sound from 0-1000000 Hz in one minute(below)

Other Sound Math:

Make a match Box sing like Sinatra

The Curious Nature of Drummers’ Brains

Headbanger Maths

Pump Up the volume or Knock, Knock Knockin on Your skull wall!

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Toilet Paper FUN FACTS Maths

June 1, 2021

Mathspig is in Melbourne, Australia. We’re in Lockdown. AGAIN!

And toilet paper has disappeared off the supermarket shelves. AGAIN.

So today we are doing maths based entirely on toilet paper using information from the Toilet Paper Fun Facts website. Yes! It exists here.

Toilet Paper Fun Facts Website

Protractor Wind Speed Calculator

POP UP ANS Q 1 & 2 Yr 7&8 Toilet Paper fun facts

Traxxas XO-1 Website

Pythagoras Equation Diagram here

Here is the Sine Rule (Watch 1.5 mins)

Check sine curve here:

Listen to sine curve here:

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Godzilla vs Kong 2021: do the math! … USA Units

January 25, 2021

METRIC version here.

This is the teaser trailer for the Godzilla vs Kong movie out in MAY, 2021. The voiceover is a poem by UK poet W. B. Yeats called The Second Coming.

The poem is a truly horrifying reflection on WW1.

What would happen if a middle school student grew as much as GODZILLA!!!!!!

Might need bigger chairs at school!!!

 The problem for the 2021 film Godzilla vs Kong is that Kong has never been as big as Godzilla even in the obscure 1962 Japanese movie King Kong vs Godzilla (below).

So either The Zilla will have to shrink or Kong will have to grow for the 2021 film.  BUT HOW MUCH should Kong grow? Remember Kong was still a teenager in Kong Skull Island (2017) so he was still growing.

OR

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Godzilla vs Kong 2021: Do the maths! … METRIC units

January 25, 2021

Post using USA UNITS here.

This is the teaser trailer for the Godzilla vs Kong movie out in MAY, 2021. The voiceover is a poem by UK poet W. B. Yeats called The Second Coming.

The poem is a truly horrifying reflection on WW1.

What would happen if a middle school student grew as much as GODZILLA!!!!!!

Might need bigger chairs at school!!!

The problem for the 2021 film Godzilla vs Kong is that Kong has never been as big as Godzilla even in the obscure 1962 Japanese movie King Kong vs Godzilla (below).

So either The Zilla will have to shrink or Kong will have to grow for the 2021 film.  BUT HOW MUCH should Kong grow? Remember Kong was still a teenager in Kong Skull Island (2017) so he was still growing.

OR