00:01
Okay, so from, look at the graph.
00:05
From the knowledge, we have learned before in similar triangle, we can write an equation like this.
00:24
10 over r equals 20 over h.
00:31
Okay? so from this equation, we can get, we get h equals 2r, right? okay, so the volume of field water is just the volume of the coin.
01:05
It's just the volume of this small coin.
01:07
Okay, so this smaller coin is 1 over 3 times pi times r squared times h.
01:21
Okay, so since we know that h equals to r, so we can plug into this expression, so i get one third times pi times r square times two r and one third times so i have two over three times pi times r to the third power okay so this is the volume of the section which is filled by water okay okay uh sorry i made a mistake so uh we should express this equation in terms of h okay uh in term of h okay uh in term i in terms of h, yes...