浮 - Protect a Child from Drowning: Use FLOATies

Readings & Meanings:

う (かぶ) to float, to come to mind

ふ

う (く)

to float, to be left over

Common Usage:

浮き輪

浮き沈み

浮力

浮く

Examples:

海で溺れそうになっている人に浮き輪を投げた。

太宰治は浮き沈みの多い人生を送った。

船は浮力を利用して浮かんでいる。

Translations:

They threw a floatation ring to the person drowning in the ocean.

Osamu Dazai was sent many ups and downs in his life.

Boats use floatation devices to float.

Radicals:

Another obvoius one on the left: San-zui tells us that water (水) is involved. Apparently the 孚 on the right is for phonetics. 孚 has a pictograph of a hand above a child (子) and has the meaning of "encase, nourish".

References:

http://www.kanjinetworks.com/pnetwork/POG.html#POG10
http://www.thejapanesepage.com/kanji/kanji/u.htm