Cups A and B are cone shaped and have heights of 12 cm and 18 cm and openings with radii of 6 cm and 4 cm, respectively. If cup B is full and its contents are poured into cup A, will cup A overflow? If not how high will cup A be filled?

1 Answer
Apr 9, 2018

10.48 cm high of cup A will be filled

Explanation:

Height and radius of cup A is h_a=12 cm , r_a=6 cm

Volume om cone is 1/3*pi*r^2*h :.V_a=1/3*pi*6^2*12 or

V_a~~ 452.39 cubic cm.

Height and radius of cup B is h_b=18 cm , r_b=4 cm

:.V_b=1/3*pi*4^2*18 or V_b~~ 301.59 cubic cm.

Since V_a > V_b , the content will not overflow.

The ratio of radius and hight of cup A is

r/h=6/12 =1/2 . The ratio of radius and hight of water cone

is r_w/h_w=1/2 or r_w=h_w/2

The volume of water cone is V_w=301.59 cubic cm.

:.1/3*pi*r_w^2*h_w =301.59 or

1/3*pi*(h_w/2)^2*h_w =301.59 or

h_w^3= (301.59*12)/pi~~1151.99 or

h_w= root(3)1151.99 ~~ 10.48 (2dp) cm

10.48 cm high of cup A will be filled [Ans]