1. The paddling pool in the photo is 8ft diameter and 1.5 ft deep. If it was filled with oil instead of water would its mass be more or less? Calculate the difference in mass if filled with water and oil.
density of oil = 800 kgm-3
density of water = 1000 kgm-3
2. 63g of Copper contains 6 x 1023 atoms. What is the approximate size of an atom?
Density of copper = 9 gcm-3
3. Calculate the length of a 30kg reel of 5mm thick copper wire.