I have no idea and want the answers:

Boat + bowling ball = level stays the same?

Ball roll = the constant gradient is quickest?

AlecBG 31 minutes ago | parent | next [-]

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

	▲	robocat 3 minutes ago \| parent \| next [-]
		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?
	▲	CodesInChaos 26 minutes ago \| parent \| prev [-]
		Depends on the shape of the dip. It increases the speed, but also the distance to travel.

14 minutes ago | parent | prev [-]

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