Banner 0
Banner 1
Banner 2
Banner 3
Banner 4
Banner 5
Banner 6
Banner 7
Banner 8

Q.

A well with 10 m   inside diameter is dug 8.4 m   deep. Earth taken out of it is spread all around it to a width of 7.5 m   to form an embankment. Find the height of the embankment.


see full answer

High-Paying Jobs That Even AI Can’t Replace — Through JEE/NEET

🎯 Hear from the experts why preparing for JEE/NEET today sets you up for future-proof, high-income careers tomorrow.
An Intiative by Sri Chaitanya

a

1.6m

b

2.8m

c

4.3m

d

3.2m 

answer is A.

(Unlock A.I Detailed Solution for FREE)

Best Courses for You

JEE

JEE

NEET

NEET

Foundation JEE

Foundation JEE

Foundation NEET

Foundation NEET

CBSE

CBSE

Detailed Solution

It is given a well of diameter 10 m, depth 8.4 m and width of embankment is 7.5 m.
Question Image Since, radius = Diameter 2    So, radius (r) is,
  r= 10 2 r=5 m  
Volume = π r 2 h  
Volume= 22 7 × 5 2 ×8.4  
Volume= 22 7 ×5×5×8.4  
Volume=660 m 3   Now,
Width of the embankment =7.5  m
Inner radius = Radius of a cylindrical well = 5 m
Outer radius = Width of embankment + Radius of cylindrical well
Outer radius = 7.5 m + 5 m
Outer radius =12.5 m
Since, Area of the material contained in a hollow cylindrical shell =π R 2 r 2   So, Area of the embankment = π R 2 r 2   Area of the embankment= 22 7 12.5 2 5 2      Area of the embankment =412.5  m 2    Volume of the embankment = Area of the embankment×height of the embankment  =π R 2 r 2 h   Volume of embankment = Volume of the earth that dugout = 660 m 3  
So, Height of embankment = Volume of embankment Area of embankment  
Height of embankment= 660 412.5 Height of embankment=1.60m  
Therefore, the height of the embankment is 1.6 m.
Hence option (1) is correct.
 
Watch 3-min video & get full concept clarity

Ready to Test Your Skills?

Check your Performance Today with our Free Mock Test used by Toppers!

Take Free Test

score_test_img

Get Expert Academic Guidance – Connect with a Counselor Today!

whats app icon