Very important question of mensuration including
very important concept of it.need solution!
Rd sharma class 10 maths exercise-16.1 mensuration.
we have to find the radius and slant height of the heap
a cylindrical bucket, 32 cm high and
18 cm of radius of the base, is filled with sand.
This bucket is emptied on the ground and a conical heap
of sand is formed. If the height of the conical heap is
24 cm.
Given,
Height of the cylindrical bucket = 32 cm
Radius of the cylindrical bucket = 18 cm
Height of conical heap = 24 cm
We know that,
Volume of cylinder = π × r2 × h
And, volume of cone = 1/3 π × r2 × h
Then, from the question
Volume of the conical heap = Volume of the cylindrical bucket
1/3 π × r2 × 24 = π × 182 × 32
r2 = 182 x 4
r = 18 x 2 = 36 cm
Now,
Slant height of the conical heap (l) is given by
l = √(h2 + r2)
l = √(242 + 362) = √1872
l = 43.26 cm
Therefore, the radius and slant height of the conical heap are 36 cm and 43.26 cm respectively.