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TIER 8 — CHALLENGE 001 — The Thermal Plateau Problem - Printable Version

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TIER 8 — CHALLENGE 001 — The Thermal Plateau Problem - Leejohnston - 11-14-2025

[border]TIER 8 — Advanced Modelling[/border]

Tier 8 — Challenge 001 — The Thermal Plateau Problem

A metal plate is heated at the centre and cools toward the edges. 
The temperature at a distance r from the centre is modelled by:

T® = 180 − 25 ln(1 + r)

Where:
• T® is temperature in °C 
• r is distance in centimetres (0 ≤ r ≤ 10)

Questions:

1. What is the temperature at r = 6 cm? 
2. At what distance r does the plate reach **120°C**? 
  (Solve exactly or with a calculated approximation.) 
3. The safe operating region requires temperatures under 110°C. 
  For what range of r is the plate unsafe?

Explain your reasoning clearly.



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Thread title: 
Tier 8 Attempt — YourUsername — Challenge 001