A closed cylindrical tank of radius 7m and height 3m is made from a sheer of metal. How much sheet of metal is required?

A cylindrical tub of radius 5 cm and length 9.8 cm is full of water. A solid is in the form of a right circular cone mounted on a hemisphere is immersed into the tub. If the radius of the hemisphere is 3.5 cm and the height of the cone outside the hemisphere is 5 cm, find the volume of water left on the tub. (Use pi = 22/7 )

Water flows through a circular pipe whose internal diameter is 2 cm at the rate of 0.7 m per second into a cylindrical tank, the radius of whose base is 40 cm. By how much will the level of water rise in the tank in half an hour.

An oil funnel made of tin sheet consists of a 10cm long cylindrical portion attached to a frustum of a cone.If the total height is 22cm,diameter of the cylindrical portion is 8 cm and the diameter of the top of the funnel is 18 cm,find thev area of the tin sheet required to made the funnel(seeFig.13.25).

The rain water from a roof 22 m xx 20 m drains into a cylindrical vessel having diameter of base 2 m and height 3.5 m. If the vessel is just full, find the height of the rainfall .

A circus tent is cylindrical height of 3 m and conical above it. If its base radius is 52.5 m and slant height of the conical portion is 53 m, find the area of the convex required to make a tent.

A 70 kg man stands in contact against the inner wail of a hollow cylindrical drum of radius 3 m rotating about its vertical axis with 200 rev/min. The coefficient of friction between the wall and his clothing is 0.15. What is the minimum rotational speed of the cylinder to enable the man to ' remain stuck to the wall (without falling) when the floor is suddenly removed?

A farmer connects a pipe of internal diameter 20cm from a canal into a cylindrical tank in her field,which is 10 m in diameter and 2 m deep.If water flows through thr pipe at the rate of 3 km/h,in how much time will the tank be filled?

A metallic sphere of radius 10.5cm is melted and then recast into small cones each of radius 3.5cm and height 3cm.The number of such cone is__-

A solid metallic sphere of diameter 21 cm is melted and recast into a number of smaller cones each of diameter 7 cm and height 3 cm. Find the.number of cones so formed

A mail bag is dropped into a post office, from an areoplane flying horizontally with a velocity 72hm/hr at height of 490m from the ground. How far must the plane be from the post office so that it may directly fall into the post office ?