Advertisements
Advertisements
प्रश्न
How many balls each of radius 1 cm can be made by melting a bigger ball whose diameter is 8 cm?
उत्तर
Diameter of bigger ball = 8 cm
Therefore, Radius of bigger ball = 4 cm
Volume = `4/3pir^3`
= `4/3pi xx 4 xx 4 xx 4`
= `(256pi)/3cm^3`
Number of balls = `(( 256pi)/3)/((4pi)/3)`
= `(256pi)/3 xx 3/(4pi)`
= 64
APPEARS IN
संबंधित प्रश्न
A right circular cylinder just encloses a sphere of radius r (see figure). Find
- surface area of the sphere,
- curved surface area of the cylinder,
- ratio of the areas obtained in (i) and (ii).
On a map drawn to a scale of 1: 50,000, a rectangular plot of land ABCD has the following dimensions. AB = 6 cm; BC = 8 cm and all angles are right angles. Find:
1) the actual length of the diagonal distance AC of the plot in km.
2) the actual area of the plot in sq. km.
A solid cone of radius 5 cm and height 8 cm is melted and made into small spheres of radius 0.5 cm. Find the number of spheres formed.
The dome of a building is in the form of a hemisphere. Its radius is 63 dm. Find the cost of
painting it at the rate of Rs. 2 per sq. m.
A spherical ball of lead has been melted and made into identical smaller balls with radius equal to half the radius of the original one. How many such balls can be made?
Metallic spheres of radii 6 cm, 8 cm and 10 cm respectively are melted and recasted into a single solid sphere. Taking π = 3.1, find the surface area of the solid sphere formed.
Total volume of three identical cones is the same as that of a bigger cone whose height is 9 cm and diameter 40 cm. Find the radius of the base of each smaller cone, if height of each is 108 cm.
A hemi-spherical bowl has negligible thickness and the length of its circumference is 198 cm. Find the capacity of the bowl.
Find the maximum volume of a cone that can be carved out of a solid hemisphere of radius r cm.
Find the radius of a sphere whose surface area is 154 cm2.
If a sphere is inscribed in a cube, find the ratio of the volume of cube to the volume of the sphere.
Mark the correct alternative in each of the following:
In a sphere the number of faces is
If the surface area of a sphere is 144π m2, then its volume (in m3) is
A sphere is placed inside a right circular cylinder so as to touch the top, base and lateral surface of the cylinder. If the radius of the sphere is r, then the volume of the cylinder is
Find the length of the wire of diameter 4 m that can be drawn from a solid sphere of radius 9 m.
A conical tent is to accommodate 77 persons. Each person must have 16 m3 of air to breathe. Given the radius of the tent as 7 m, find the height of the tent and also its curved surface area.
Find the volume and surface area of a sphere of diameter 21 cm.
The cylinder of radius 12 cm have filled the 20 cm with water. One piece of iron drop in the stands of water goes up 6.75 cm. Find the radius of sphere piece.
A solid sphere is cut into two identical hemispheres.
Statement 1: The total volume of two hemispheres is equal to the volume of the original sphere.
Statement 2: The total surface area of two hemispheres together is equal to the surface area of the original sphere.
Which of the following is valid?
