This question is from mensuration chapter of rd sharma Class 10, chapter 16 .

I need solution of this question . In this question we have to find diameter of cylindrical vessel.

**A cylindrical vessel having diameter equal to its height is full of water which is poured into two identical cylindrical vessels with diameter 42 cm and height 21 cm which are filled completely.**

The diameter of the cylinder = the height of the cylinder

â‡’ h = 2r, where h â€“ height of the cylinder and r â€“ radius of the cylinder

We know that,

Volume of a cylinder = Ï€r2h

So, volume of the cylindrical vessel = Ï€r22r = 2Ï€r3 (as h = 2r)â€¦.. (i)

Now,

Volume of each identical vessel = Ï€r2h

Diameter = 42 cm, so the radius = 21 cm

Height = 21 cm

So, the volume of two identical vessels = 2 x Ï€ 212 Ã— 21 â€¦.. (ii)

Since the volumes on equation (i) and (ii) are equal

On equating both the equations, we have

2Ï€r3= 2 x Ï€ 212 Ã— 21

r3 = (21)3

r = 21 cm

So, d = 42 cm

Therefore, the diameter of t he cylindrical vessel is 42 cm