March 4, 2013

November 1, 2012

## Zombie Maths 4: Simultaneous Equations

December 13, 2011

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# The Laughing Mathematician.

July 4, 2011

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## 5. You can jump out of an airplane that is about to crash and catch the baddie who took the last parachute.

November 16, 2009

The names Bond, James Bond. In Moonraker  with Roger Moore (1979) 007 jumps out of a plane without a parachute to avoid an assassination attempt. He catches up with, Jaws, arch-baddie, in mid-air and takes his parachute. Jaws survives his fall by landing on a big top circus tent.

In Point Break with FBI agent Johnny Utah, Keanu Reeves, leaps from a skydiving plane after Patrick Swayzes’ characer, Bohdi, who has taken the last parachute. Utah catches Bohdi in mid-air, and after a tense confrontation with a gun, both survive using Bodhi’s chute.

There are more movie and real life stories at Free Fall Website:

http://www.greenharbor.com/fffolder/fiction.html

What’s the deal? Can Utah really catch Bohdi?

Here are some stats from the  Free Fall Maths link:

http://www.greenharbor.com/fffolder/math.html

Note: We’ll assume Bhodi and Utah have equal horizontal velocities (plane exit velocity plus wind) so the following calculations only involve the vertical or falling velocity. The terminal velocities used for Bhodi and Utah are realistic estimates. We do not need the sky divers weight for these calculations but it can impact on terminal velocity so I have included this data and chute open data for general interest.

## 10 You can out run a lava flow

November 16, 2009

Every volcano disaster movie from Volcano (1997) with Tommy Lee Jones to Dante’s Peak (1997) with Pierce Brosnan someone somewhere tries to out run a lava flow. Is this possible?

The answer is maybe. You will find everything you want to know about lava flows @ http://volcano.oregonstate.edu/

On January 10,1977, at Nyiragongo lava sprang from the sides of the volcano moving at speeds up to 40 miles per hour (60 km/hr). About 70 people were killed.

Measuring the temperature of lava. Photograph by R.L. Christiansen, U.S. Geological Survey, January 9, 1973.
The fastest Lava flows recorded were in Hawaiiin 1950 when Mauna Loa erupted. The lava traveled at 6 miles (10 kilometers) per hour through thick forest. But once the lava flows became established and good channels developed, the lava in the channels was flowing at up to 60 km/hour (97 kph).

Speed of average sprinter = 19 – 24 kph

Can you out run lava?

Work it out mathspigs. You are 300m ahead of the lava flow and you need to get up a hill to escape, which is 1000m away. The lava is flowing at 30 kph and you are running at 18 kph.

Will you make it??????