हिंदी

How many silver coins, 1.75 cm in diameter and of thickness 2 mm, must be melted to form a cuboid of dimensions 5.5 cm × 10 cm × 3.5 cm? - Mathematics

Advertisements
Advertisements

प्रश्न

How many silver coins, 1.75 cm in diameter and of thickness 2 mm, must be melted to form a cuboid of dimensions 5.5 cm × 10 cm × 3.5 cm? [Use  π=22/7]

उत्तर

Coins are cylindrical in shape.

Height (h1) of cylindrical coins = 2 mm = 0.2 cm

Radius (r) of circular end of coins = 1.75/2 =0.875 cm

Let n coins be melted to form the required cuboids.

Volume of n coins = Volume of cuboids

nxπxr2xh1 = lxbxh

n x π x (0.875)2 x 0.2 = 5.5 x 10 x 3.5

`n = (5.5xx10xx3.5xx7)/((0.875)^2xx0.2xx22) = 400`

Therefore, the number of coins melted to form such a cuboid is 400.

shaalaa.com
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 13: Surface Areas and Volumes - Exercise 13.3 [पृष्ठ २५१]

APPEARS IN

एनसीईआरटी Mathematics [English] Class 10
अध्याय 13 Surface Areas and Volumes
Exercise 13.3 | Q 6 | पृष्ठ २५१

वीडियो ट्यूटोरियलVIEW ALL [1]

संबंधित प्रश्न

A solid frustum is of height 8 cm. If the radii of its lower and upper ends are 3 cm and 9 cm respectively, then its slant height is


If two solid-hemisphere s of same base radius r are joined together along their bases , then curved surface area  of this new solid is 


Metallic spheres of radii 6 cm, 8 cm and 10 cm, respectively are melted to form a single solid sphere. Find the radius of the resulting sphere.


During conversion of a solid from one shape to another, the volume of the new shape will ______.


A cylindrical bucket, 32 cm high and with radius of base 18 cm, is filled with sand. This bucket is emptied out on the ground and a conical heap of sand is formed. If the height of the conical heap is 24 cm, find the radius and slant height of the heap.


A solid cylinder of radius r and height h is placed over other cylinder of same height and radius. The total surface area of the shape so formed is ______.


During conversion of a solid from one shape to another, the volume of the new shape will ______.


A solid metallic hemisphere of radius 8 cm is melted and recasted into a right circular cone of base radius 6 cm. Determine the height of the cone.


A solid piece of metal in the form of a cuboid of dimensions 11 cm × 7 cm × 7 cm is melted to form 'n' number of solid spheres of radii `7/2` cm each. Find the value of n.


A company deals in casting and moulding of metal on orders received from its clients.

In one such order, company is supposed to make 50 toys in the form of a hemisphere surmounted by a right circular cone of the same base radius as that of hemisphere. If the radius of the base of the cone is 21 cm and height is 28 cm.

  1. find the volume of 50 toys:
  2. fine the ratio of the volume of hemisphere to the volume of cone.

Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×