12 14 A student investigated the terminal velocity of steel spheres falling through oil. The student obtained the following results. radius of steel sphere = 1.50 mm volume of steel sphere = 1.41 × 10−8 m3 mass of steel sphere = 1.10 × 10−4 kg maximum speed of sphere = 0.849 m s−1 The student had the following table. Type of oil Density at 26 °C / kg m−3 Viscosity at 26 °C / Pa s Corn 918 0.0447 Hazelnut 918 0.0504 Sunflower 918 0.0414 (a) Identify which type of oil the student used. (4) .................................................................................................................................................................................................................................................. .................................................................................................................................................................................................................................................. .................................................................................................................................................................................................................................................. .................................................................................................................................................................................................................................................. .................................................................................................................................................................................................................................................. .................................................................................................................................................................................................................................................. .................................................................................................................................................................................................................................................. .................................................................................................................................................................................................................................................. .................................................................................................................................................................................................................................................. .................................................................................................................................................................................................................................................. Turn over 13 (b) The values in the table are for oil at 26 °C. Explain the effect of carrying out the investigation with oil at a lower temperature. (2) .................................................................................................................................................................................................................................................. .................................................................................................................................................................................................................................................. .................................................................................................................................................................................................................................................. .................................................................................................................................................................................................................................................. (Total for Question 14 = 6 marks)