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

**Other Sound Math:**

**Make a match Box sing like Sinatra**

**The Curious Nature of Drummers’ Brains**

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

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

**Other Sound Math:**

**Make a match Box sing like Sinatra**

**The Curious Nature of Drummers’ Brains**

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

**In 2014 Winter Olympics Annette Gerristen (below) lost the Gold Medal in the 1000 m Women’s speed skate competition by 0.02 seconds.**

**Italy’s Arianna Fontana wins the 500 m Speed Skating 2018 Olympic Gold Medal in 42.569 seconds ahead of Yara van Kerkhof of the Netherlands and Kim Boutin of Canada. **

**Apollo Ono (below) competed in the 1500m men’s speed skating. He has won 8 Olympic Medals.**

**If a speed skater lost the Gold Medal by 0.001 seconds, the smallest measured time segment at the Olympics, they would be:**

**behind the winner. That is less than the length of a small fingernail.**

With wildfires in Texas and now Australia is facing the fire season, it is time to think about fire fighter maths.

On **5 ^{th} 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.

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

t_{1 }=

t_{2} =

t_{3}=

Average your time:

t_{av} = (t_{1 } + t_{2} + t_{3)}/ 3 =

Your Speed S = 10/t_{av} = ……… m/sec

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

__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.

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**.

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**.

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**.

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**.

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.

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.

The follicle diagram (above) came from bgoffforensics blog. More on hair growth rates here.

The growth rates of 1.25 cm/month or 0.5 inches/month are rounded off. Calculations using these growth rates will produce different answers for very large numbers (as above). Read more about the above story in the Daily Mail, UK here. By the way, Asha has been growing her hair for 25 years. Her hair weighs 3 stone or 19 kg. You can find more hair records including the World’s longest ear hair here.

Natasha lives in Rio de Janeiro, Brazil. Read more about Natasha in the Daily Mail here. Once again Mathspig has rounded off the length of hair for easy calculation. The Daily Mail puts Natasha’s ‘mane’ at 5 feet 2 inches or 157 cm. This is the length of hair to be cut off. So Mathspig adjusted the length to 180cm or the approx length of her longest hair.