Answer:
h = 5 cm
Step-by-step explanation:
Given that,
The volume of ice-cream in the cone is half the volume of the cone.
Volume of cone is given by :
[tex]V_c=\dfrac{1}{3}\pi r^2h[/tex]
r is radius of cone, r = 3 cm
h is height of cone, h = 6 cm
So,
[tex]V_c=\dfrac{1}{3}\pi (3)^2\times 6\\\\V_c=18\pi\ cm^3[/tex]
Let [tex]V_i[/tex] is the volume of icecream in the cone. So,
[tex]V_i=\dfrac{18\pi}{2}=9\pi\ cm^3[/tex]
Let H be the depth of the icecream.
Two triangles formed by the cone and the icecream will be similiar. SO,
[tex]\dfrac{H}{6}=\dfrac{r}{3}\\\\r=\dfrac{H}{2}[/tex]
So, volume of icecream in the cone is :
[tex]V_c=\dfrac{1}{3}\pi (\dfrac{h}{2})^2(\dfrac{h}{3})\\\\9\pi=\dfrac{h^3}{12}\pi\\\\h^3=108\\\\h=4.76\ cm[/tex]
or
h = 5 cm
So, the depth of the ice-cream is 5 cm.