On a very cold day at a temperature of –12°C, a power line made of aluminum between two support towers measures exactly 150.56m. You go out on a hot day and measure the power line to be exactly 150.71m. What is the temperature (in °C) outside? The linear expansion coefficient of aluminum is 2.4×10^-5.

(a) A horizontal steel I-beam of a cross-sectional area of 0.041 m² is rigidly connected to two fixed vertical supports. If the beam was installed when the temperature was 25°C

(b) Is the ultimate strength of the steel exceeded?

(c) What stress is developed if the concrete beam has a cross-sectional area of 0.15m²? Will it fracture?

(I) The Eiffel Tower (Fig. 17–20) is built of wrought iron approximately 300 m tall. Estimate how much its height changes between January (average temperature of 2°C) and July (average temperature of 25°C). Ignore the angles of the iron beams and treat the tower as a vertical beam.

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If a steel band were to fit snugly around the Earth’s equator at 25°C but then was heated to 55°C, how high above the Earth would the band be (assume equal everywhere)?

A precise steel tape measure has been calibrated at 14°C. At 37°C,

(b) what will be the percentage error?