Yes you can make something that sinks float! All you have to do is add a good amount of salt.
Answer:
Objects will only float in liquid that is denser than the object. This gives you two options. You can either:
To increase the density of the liquid you can dissolve a solute into the liquid. Salt is one option, but a nice thick sugar solution would be even better. If the only criteria is that the object must float you could replace the liquid with very high density fluid like Mercury or molten metal. If the density is close to being "dense enough" simply cooling the liquid might be enough of a change.
To decrease the density of the object you want to float is harder. You can change the shape of the object so it becomes like a boats hull or an empty gasoline drum.
When it sinks.
to float something there must be some hollow space and it should not let the water get there
No, Fimo does not float in water. It is a type of polymer clay that is dense and sinks in water.
What causes it to sink or float is the density. The density of water is 1.0. If the object's density is more 1.0 then it sinks, but if the object's density is less then 1.0 then the object will float.
No, it sinks.
Depends on what they're dropped into. Water - no. But drop them into something that's denser than aluminium and they will float.
It sinks
No, it sinks.
Float
All pure metal sinks, only by entrapping air in waterproof compartments can you make it (ships) float.
No, ironwood does not float. It is a dense and heavy type of wood that sinks in water.
density!