ACT-SCIENCE-P4

According to Study 2, the thermal conductivity of rock salt measured at a temperature of 500°C would be closest to which of the following values?

• 1.0 W/m°C
• 2.0 W/m°C
• 3.5 W/m°C
• 4.0 W/m°C

According to Study 3, if another set of temperatures had been calculated for a time 1,000,000 years in the future, the calculated temperature increase in any of the 4 rock types would most likely be closest to:

• 0°C
• 10°C.
• 20°C.
• 30°C.

Welded tuff (another rock type) has a thermal conductivity of 1.8 W/m°C at 25°C. If measurements of the temperature of this rock type adjacent to SF canisters were taken as in Study 1, the recorded temperature would be closest to:

• 100°C.
• 110°C.
•  120°C.
• 130°C.

According to the results of Study 1, which of the following best describes the relationship between thermal conductivity and rock temperature? As thermal conductivity increases, the rock temperature recorded adjacent to buried SF canisters:

• decreases only.
• increases only.
• increases, then decreases.
• remains the same.

Based only on the information provided, which of the following rock types would be the safest in which to bury SF ?

• Rock salt
• Granite
• Basalt
• Shale

Which of the following procedures, in addition to Studies 1, 2, and 3, would best test whether the amount of heat generated by SF is related to the mass of the SF ?

• Following the design of Study 1 but using concrete canisters containing 0.4 metric tons of SF
• Following the design of Study 1 but using stainless steel canisters containing 0.8 metric tons of SF
• Following the design of Study 2 but determining the thermal conductivities of twice as much of each rock type
• Following the design of Study 3 but determining the rock temperatures 0.5 km from the sites of SF burial