A cylindrical bucket 32 CM high and with radius of base 18 cm ,is filled with sand. This bucket is empited on the ground and a conical heap of sand is formed. If the high of the conical heap is 24 cm, find the radius and slant height of the heap??
Answers
Solution
Height of cylindrical bucket(h1)=32 cm
Radius of the base of the bucket (r1)=18 cm
∴Volume of the sand in the cylindrical bucket=πr12h1
Height of conical heap (h2)=24 cm
let the radius of the conical heap=r2
∴Volume of the sand in conical heap=31πr22h2
According to the question
The volume of the sand in the cylindrical bucket=Volume of the sand in the conical shape
πr12h1=31πr22h2
⇒π×(18)2×32=31π×r22×24
⇒r22=243×182×32
⇒r
Answer:
Height of cylindrical bucket(h
1
)=32 cm
Radius of the base of the bucket (r
1
)=18 cm
∴Volume of the sand in the cylindrical bucket=πr
1
2
h
1
Height of conical heap (h
2
)=24 cm
let the radius of the conical heap=r
2
∴Volume of the sand in conical heap=
3
1
πr
2
2
h
2
According to the question
The volume of the sand in the cylindrical bucket=Volume of the sand in the conical shape
πr
1
2
h
1
=
3
1
πr
2
2
h
2
⇒π×(18)
2
×32=
3
1
π×r
2
2
×24
⇒r
2
2
=
24
3×18
2
×32
⇒r
2
2
=18
2
×4
⇒r
2
=18×2=36cm
Slant height of heap=
r
2
2
+h
2
2
⇒
36
2
+24
2
⇒
1296+576
⇒
1872
⇒
144×13
⇒12
13
cm.