Question

a glass cylinder with diameter 20cm has water to a height of 9 CM. a metal cube of 8 cm edge is immersed in it completely calculate the height by which water will be rise in the cylinder

Answer 1

let water rises is h..water in cylinder forms a cylinder of height hcm and radius 10cm.
volume of water displaced=volume of the cube of edge 8cm
πr²h=8³
3.14×10²×h=8×8×8
314×h=512
h=512÷312
h=1.6cm

Answer 2

Answer:

H = 9 cm

diameter = 20 cm so,radius = 10 cm

side of the cube = 8 cm

Total volume of the cylinder

(after cube is immersed) = Volume of water in cylinder + Volume of water displaced or volume of the cube

= 22/7*10*10*9 + 8*8*8

= 19800/7 + 512

= 2828.57 + 512

= 3340.57 cu cm

Now, height of water, h1 can be found by equating πr²h1 with this volume.

So,

22/7*10*10*h1 = 3340.57

h1 = (3340.57 × 7)/2200

h1 = 23383.99/2200

Height = 10.63 cm

Rise in the water level in the cylinder

= h1 - h

= 10.63 - 9

= 1.63 cm