CameraIcon
CameraIcon
SearchIcon
MyQuestionIcon


Question

The surface area of a solid metallic sphere is $$\displaystyle 1256cm^{2}$$ it is melted and recast into solid right circular cones of radius 2.5 cm and height 8 cm ; then the no. of cones cast $$\displaystyle (\pi =3.14)$$


A
40
loader
B
25
loader
C
48
loader
D
80
loader

Solution

The correct option is D 80
Let the radius of the solid metallic sphere be $$r$$cm
$$\therefore 4\pi r^2=1256$$
$$=>r^2=\frac{1256}{4\pi}$$
$$=>r\simeq10$$cm
Now,
Volume of the solid metallic sphere=$$\frac{4}{3}\pi r^3$$
                                                             =$$\frac{4}{3}\times \frac{22}{7}\times 10^3$$
                                                             =$$4190.5 cm^3$$
Volume of the solid right circular cone=$$\pi r^2\frac{h}{3}$$
                                                                 =$$\pi(2.5)^2\times \frac{8}{3}$$
                                                                 =$$52.36 cm^3$$
$$\therefore$$ Number of cones casted=$$\frac{4190.5}{52.36}$$
                                           $$\simeq 80$$ 

Mathematics

Suggest Corrections
thumbs-up
 
0


similar_icon
Similar questions
View More


similar_icon
People also searched for
View More



footer-image