Question

Rain water, which falls on a flat rectangular surface of length 6cm and breath 4m is
transferred into a cylindrical vessel of internal radius 20cm. What will be the height of
water in the cylindrical vessel if a rainfall of 1cm has fallen____?

Answer 1

Given length of rectangular surface =6cm

Breath of rectangular surface = 4cm

Height (h) 1cm

Volume of a flat rec tan gular surface = lbh

= 6000 x 400 x 1

Volume = 240000cm³     .............(1)

Given radius of cylindrical vessel = 20cm

Let height off cylindrical vessel be h₁

Since rains are transferred to cylindrical vessel.

So equating (1) with (2)

Volume of cylindrical vessel = ${\displaystyle \pi r_1^2{h}_1}$

${\displaystyle =\frac{22}{7}{\left(20\right)}^2\times h_1}$        .............(2)

24000${\displaystyle =\frac{22}{7}{\left(20\right)}^2\times h_1}$

⇒h₁ = 190.9cm

∴height of water in cylindrical vessel = 190 9cms