MyQuestionIcon

1

You visited us 1 times! Enjoying our articles? Unlock Full Access!

Surface Area of Combined Figures

The cross-sec...

Question

The cross-section of a railway tunnel is a rectangle 6 m broad and 8 m high surmounted by a semi-circle as shown in the figure. The tunnel is 35 m long. Find the cost of plastering the internal surface of the tunnel (excluding the floor) at the rate of Rs. 2.25 per $m^{2}$ .

Open in App

Solution

Rectangle: Breadth $= 6 \ m, Height = 8 \ m$

Semi-circle: Radius $= 3 \ m$

Length of the tunnel $= 35 \ m$

Surface Area of the tunnel $=$ $\frac{1}{2}$ $2 \pi \times 3 \times 35 + 8 \times 35 \times 2$

$= 330 + 560 = 890 \ m^2$

Cost of plastering $= 890 \times 2.25 = 2002.5 \ Rs.$

Suggest Corrections

thumbs-up

4

Similar questions

The cross-section of a perpendicular to its length is a trapezium ABCD as shown in the figure also given that :
AM = BN; AB = 7 m; CD = 5 m. The height of the tunnel is 2.4 m. The tunnel is 40 m long. Calculate the cost of painting the internal surface of the tunnel (excluding the floor) at the rate of Rs. 5 per

m^{2}

Q. The cost of painting the internal surface of the tunnel (excluding the floor) at the rate of Rs.

5

m^{2}

Q. There is a 40m long Tunnel. The cross section of the tunnel is a semicircle with a radius 6. Find the cost of painting it at the rate of ₹2/m²

Q. The length of a semicircular tunnel is

2

k m

and diameter is

7

m

. Find the expenditure for digging the tunnel at the rate of Rs.

600

m^{3}

. Find the expenditure for plastering inner side of the tunnel at the rate of Rs.

50

m^{2}

(π = \frac{22}{7})

Q. The figure shows the cross-section of the railway tunnel. The radius OA of the circular path is

2

∠ A O B = 90^{\circ}

, calculate the height of the tunnel.

View More

Join BYJU'S Learning Program

similar_icon

Related Videos

lock

Combination of Solids

MATHEMATICS

Watch in App

explore_more_icon

Explore more

Surface Area of Combined Figures

Standard X Mathematics

Join BYJU'S Learning Program

CrossIcon