Answer:Aluminium
Explanation:
Given
Aluminium ball sinks after placing inside the water while wooden block floats.
Buoyancy on a body is given by
[tex]volume\ inside\ the\ water \times density\ of\ fluid\times g[/tex]
here [tex]\rho _{Al}>\rho _{water}[/tex]
thus aluminium ball sinks
but for
[tex]\rho _{wood}<\rho _{water}[/tex]
only a part of wood is under the water i.e. not whole volume is not under water therefore net buoyancy is less in case of wood
