Chapter 13 – Surface Areas and Volumes
A wooden toy rocket is in the shape of a cone mounted on a cylinder, as shown in figure. The height of the entire rocket is 26cm, while the height of the conical part is 6cm. The base of the conical portion has a diameter of 5cm, while the base diameter of the cylindrical portion is 3cm. If the conical portion is to be painted orange and the cylindrical portion yellow, find the area of the rocket painted with each of these colours. (Take π=3.14)
06
Oct
A wooden toy rocket is in the shape of a cone mounted on a cylinder, as shown in figure. The height of the entire rocket is 26cm, while the height of the conical part is 6cm. The base of the conical portion has a diameter of 5cm, while the base diameter of the cylindrical portion [...]
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A wooden toy rocket is in the shape of a cone mounted on a cylinder ,
as shown in figure. The height of the entire rocket is 26cm ,
find the area of the rocket painted with each of these colours. (Take π=3.14) ,
while the base diameter of the cylindrical portion is 3cm. If the conical portion is to be painted orange and the cylindrical portion yellow ,
while the height of the conical part is 6cm. The base of the conical portion has a diameter of 5cm ,
A decorative block shown in figure, is made of two solids- a cube and a hemisphere. The base of the block is a cube with edge 5cm, and the hemisphere fixed on the top has a diameter 4.2cm. Find the total surface area of the block (Take π=22/7)
06
Oct
A decorative block shown in figure, is made of two solids- a cube and a hemisphere. The base of the block is a cube with edge 5cm, and the hemisphere fixed on the top has a diameter 4.2cm. Find the total surface area of the block (Take π=22/7) A decorative block shown in figure and [...]
Rasheed got a playing top (lattu) as his birthday present, which surprisingly had no colour on it. He wanted to colour it with his crayons. The top is shaped like a cone surmounted by a hemisphere. The entire top is 5cm in height and the diameter of the top is 3.5cm. Find the area he has to colour (Take π=22/7)
06
Oct
Rasheed got a playing top (lattu) as his birthday present, which surprisingly had no colour on it. He wanted to colour it with his crayons. The top is shaped like a cone surmounted by a hemisphere. The entire top is 5cm in height and the diameter of the top is 3.5cm. Find the area he [...]
An oil funnel made of tin sheet consists of a 10 cm long cylindrical portion attached to a frustum of a cone. If the total height is 22 cm, diameter of the cylindrical portion is 8 cm and the diameter of the top of the funnel is 18 cm, find the area of the tin sheet required to make the funnel .
06
Oct
An oil funnel made of tin sheet consists of a 10 cm long cylindrical portion attached to a frustum of a cone. If the total height is 22 cm, diameter of the cylindrical portion is 8 cm and the diameter of the top of the funnel is 18 cm, find the area of the tin [...]
Tags:
An oil funnel made of tin sheet consists of a 10 cm long cylindrical portion attached to a frustum of a cone. If the total height is 22 cm ,
diameter of the cylindrical portion is 8 cm and the diameter of the top of the funnel is 18 cm ,
find the area of the tin sheet required to make the funnel . ,
In one fortnight of a given month, there was a rainfall of 10 cm in a river valley. If the area of the valley is 7280 km^2 , show that the total rainfall was approximately equivalent to the addition to the normal water of three rivers each 1072 km long, 75 m wide and 3 m deep.
06
Oct
In one fortnight of a given month, there was a rainfall of 10 cm in a river valley. If the area of the valley is 7280 km^2 , show that the total rainfall was approximately equivalent to the addition to the normal water of three rivers each 1072 km long, 75 m wide and 3 [...]
A cistern, internally measuring 150 cm x 120 cm x 110 cm, has 129600 cm^3 of water in it. Porous bricks are placed in the water until the cistern is full to the brim. Each brick absorbs one-seventeenth of its own volume of water. How many bricks can be put in without overflowing the water, each brick being 22.5 cm x 7.5cm x 6.5 cm
06
Oct
A cistern, internally measuring 150 cm x 120 cm x 110 cm, has 129600 cm^3 of water in it. Porous bricks are placed in the water until the cistern is full to the brim. Each brick absorbs one-seventeenth of its own volume of water. How many bricks can be put in without overflowing the water, [...]
A right-angled triangle whose sides are 3 cm and 4 cm (other than hypotenuse) is made to revolve about its hypotenuse. Find the volume and surface area of the double cone so formed. (Choose a value of π as found appropriate.)
06
Oct
A right-angled triangle whose sides are 3 cm and 4 cm (other than hypotenuse) is made to revolve about its hypotenuse. Find the volume and surface area of the double cone so formed. (Choose a value of π as found appropriate.) Two cubes each of volume 64 cm^3 are joined end to end. Find the [...]
A copper wire, 3 mm in diameter, is wound about a cylinder whose length is 12 cm, and diameter 10 cm, so as to cover the curved surface of the cylinder. Find the length and mass of the wire, assuming the density of copper to be 8.88 g per cm^3 .
06
Oct
A copper wire, 3 mm in diameter, is wound about a cylinder whose length is 12 cm, and diameter 10 cm, so as to cover the curved surface of the cylinder. Find the length and mass of the wire, assuming the density of copper to be 8.88 g per cm^3 . 3 mm in diameter [...]
A metallic right circular cone 20 cm high and whose vertical angle is 60 degree is cut into two parts at the middle of its height by a plane parallel to its base. If the frustum so obtained be drawn into a wire of diameter 16/1 cm, find the length of the wire.
06
Oct
A metallic right circular cone 20 cm high and whose vertical angle is 60 degree is cut into two parts at the middle of its height by a plane parallel to its base. If the frustum so obtained be drawn into a wire of diameter 16/1 cm, find the length of the wire. A metallic [...]
A container, opened from the top and made up of a metal sheet is in the form of a frustum of a cone of height 16cm with radii of its lower and upper ends as 8cm and 20cm respectively. Find the cost of the milk which can completely fill the container, at the rate of Rs 20 per litre. Also find the cost of metal sheet used to make the container , if it costs Rs 8 per 100 cm^2 . (Take π=3.14)
06
Oct
A container, opened from the top and made up of a metal sheet is in the form of a frustum of a cone of height 16cm with radii of its lower and upper ends as 8cm and 20cm respectively. Find the cost of the milk which can completely fill the container, at the rate of [...]