Question

Most underground train systems have a problem of high temperatures within sections of their tunnels. For example, the London underground has several sections of rail line where the tunnel temperature can be above 40 °C. The problem has become worse over the past 100 years as soil around the tunnels has gradually warmed. QUESTION Which of these heat sources could have contributed to warming soil around the tunnels deep underground? Click “Yes” or “No” in each case.

Heat source
Yes / No

Heat from the sun.
Yes / No

Heat released from the trains brakes.
Yes / No

Heat from the train engines.
Yes / No

Heat from passengers’ bodies.
Yes / No

Heat release by air friction
Yes / No




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Answer 1

Answer:

heat source = yes

heat from sun = no

heat released from the train breaks = yes

the heat from the train engines = yes

the heat from passenger's body = yes

the heat released by air friction = yes

Explanation: