1. Helium-filled balloon in the same train: How will it place itself ?
Riddle:
Train accelerates. A lamp or rubber ball will hang as shown in the upper picture
Helium-filled balloon in the same train:
How will it place itself ?
PHYS spring page 1

2. how fast did you give the answer:
(B)
A related riddle:
how fast did you give the answer:
A stone is placed on a toy boat. The stone is now moved to the water. What will happen? Result (A) or result (B) ?
Will the level of water in the container rise or sink?
And thus the whole story of Archimedes law
and buoyancy – OPPDRIFT (norwegian)
Any floating object displaces its own weight of fluid. – Archimedes of Syracuse
PHYS spring page 2

3. We have discussed one more illustration of holes: BUBBLES
Bubbles travel uppwads
Stones are falling downwards
We have discussed one more illustration of holes: BUBBLES
And
Helium-filled balloon
And thus the whole story of Archimedes law
and buoyancy – OPPDRIFT (norwegian)
Any floating object displaces its own weight of fluid. – Archimedes of Syracuse
PHYS spring page 3