Which of the following statement(s) is/are true? (I) Every substance contains heat. (II) For heat to flow between two substances, they must be at different temperatures. (III) The internal energy of a substance is equal to the kinetic energy of the molecules in the substance.
A surveyor uses a steel measuring tape that is exactly 50.000 m long at a temperature of 20∘∘C. The markings on the tape are calibrated for this temperature. (a) What is the length of the tape when the temperature is 35∘∘C? (b) When it is 35∘∘C, the surveyor uses the tape to measure a distance. The value that she reads off the tape is 35.794 m. What is the actual distance? α=1.2×10−5/∘C