| ▲ | AlecBG an hour ago | |
First one water is lower. Ball is more dense than water, in boat displaces its weight in water, in water displaces it's volume Dip for hill roll is faster | ||
| ▲ | CodesInChaos an hour ago | parent | next [-] | |
A dip increases the speed (decreasing travel time), but also the distance to travel (increasing travel time). Which of those effects dominates depends on the shape of the dip. The hill decreases speed and increases distance, so it's always slower than the straight line. | ||
| ▲ | robocat 35 minutes ago | parent | prev [-] | |
Next bail 10 litres of water from the lake into the open-topped boat. What are the effects of the 10 litres of air displaced from within the boat? | ||