Question

How many shots each having diameter 3 cm can be made from a cuboidal lead solid of dimensions 9 cm × 11cm × 12cm?

Answer 1

Volume of cuboid = lbh,

Where, l = length,

b = breadth 

And h = height

Cuboidal lead:

Length, l = 9 cm

Breadth, b = 11 cm

Height, h = 12 cm

Volume of lead = 9(11)(12) = 1188 cm³

Volume of sphere = `4/(3π"r"^3)`, where r = radius of sphere

Spherical shots,

Diameter = 3 cm

Radius, r = 1.5 cm

Volume of one shot = `4/3 × 22/7 × (1.5)^3`

= `99/7 "cm"^3` 

No. of shots can be made = `"Volume of lead"/"Volume of one shot"`

= `1188/(99/7)`

= `(1188 xx 7)/99`

= 84

Hence, the number of bullets that can be made from lead = 84.