Volume and Surface Area Questions

FACTS  AND  FORMULAE  FOR  VOLUME  AND  SURFACE  AREA  QUESTIONS

 

 

I. CUBOID

   Let length=l, breadth =b and height =h units. Then,

1. Volume = (l x b x h)

2. Surface area = 2(lb +bh + lh) sq.units

3. Diagonal =l2+b2+h2 units

 

 

II. CUBE 

Let each edge of a cube be of length a. Then,

1. Volume = a3 cubic units.

2. Surface area = 6a2 sq.units

3. Diagonal = 3a units

 

 

III. CYLINDER 

Let radius of base = r and Height (or Length) = h. Then, 

1.Volume = πr2h cubic units 

2. Curved surface area = 2πrh sq.units

3. Total surface area = 2πrh+2πr2 sq.units

 

 

IV. CONE 

Let radius of base =r and Height = h. Then, 

1. Slant height, l=h2+r2 units

 

2. Volume = 13πr2h cubic units.

 

3. Curved surface area = πrlsq.units 

 

4. Total surface area = πrl+πr2sq.units

 

 

V. SPHERE 

Let the radius of the sphere be r. Then, 

1. Volume =43πr3 cubic units

2. Surface area = 4πr2 sq.units

 

 

VI. HEMISPHERE 

Let the radius of a hemisphere be r. Then, 

1. Volume = 23πr3 cubic units.

2. Curved surface area = 2πr2 sq.units

3. Total surface area = 3πr2 sq.units

 

Q:

A cistern 6m long and 4 m wide contains water up to a depth of 1 m 25 cm. The total area of the wet surface is:

A) 49 B) 50
C) 53.5 D) 55
 
Answer & Explanation Answer: A) 49

Explanation:

Area of the wet surface = [2(lb + bh + lh) - lb] 

= 2(bh + lh) + lb 

= [2 (4 x 1.25 + 6 x 1.25) + 6 x 4]m2  

= 49m2

Report Error

View Answer Report Error Discuss

86 40753
Q:

Consider the following statements:

1) An isosceles trapezium is always cyclic.

2) Any cyclic parallelogram is a rectangle.

Which of the above statements is/are correct?

A) 1 only B) 2 only
C) Both 1 and 2 D) Neither 1 nor 2
 
Answer & Explanation Answer: C) Both 1 and 2

Explanation:

Since it is an isosceles trapezium

So angle C = angle D = x

let A = 180 –D = 180 –x (since AB is parallel to CD)

B = 180-x

A+C = 180 –x + x = 180 degrees (Property of cyclic quadrilateral)

ABCD is cyclic parallelogram with AB // CD and AD // BC

Considering angles A = C = y (Property of parallelogram) and B=D = x Also since it is cyclic A+C = B+D = 180 degrees

So x=y=90 degrees And also opposite sides are equal being a parallelogram

Thus ABCD is a rectangle

Report Error

View Answer Report Error Discuss

Filed Under: Volume and Surface Area
Exam Prep: Bank Exams

0 40057
Q:

Consider the following inequalities in respect of any triangle ABC:

1) AC –AB < BC

2) BC –AC < AB

3) AB –BC < AC

Which of the above are correct?

A) 1 and 2 only B) 2 and 2 only
C) 1 and 3 only D) 1, 2 and 3
 
Answer & Explanation Answer: D) 1, 2 and 3

Explanation:

AC-AB<BC Or AB+BC>AC

BC-AC<AB Or AB+AC>BC

AB-BC<AC Or AC+BC>AB

Sum of 2 sides of triangle is always greater than the third side

So all three statements are true

 

Report Error

View Answer Report Error Discuss

Filed Under: Volume and Surface Area
Exam Prep: Bank Exams

1 38356
Q:

Find the curved surface area (in cm2) of a right circular cylinder of diameter 14 cm and height 8 cm.

 

A) 308 B) 352
C) 327 D) 371
 
Answer & Explanation Answer: B) 352

Explanation:
Report Error

View Answer Report Error Discuss

Filed Under: Volume and Surface Area
Exam Prep: Bank Exams

0 38193
Q:

Which of the following option is CORRECT for SAS similarly criterion for the triangle ABC and DEF?

 

 

A) B)
C) D) All options are correct
 
Answer & Explanation Answer: D) All options are correct

Explanation:
Report Error

View Answer Report Error Discuss

Filed Under: Volume and Surface Area
Exam Prep: Bank Exams

0 35996
Q:

The diagonal of a rectangle is sqrt(41) cm.  and its area is 20 sq. cm. The perimeter of the rectangle must be:

A) 9 cm B) 18 cm
C) 20 cm D) 41 cm
 
Answer & Explanation Answer: B) 18 cm

Explanation:

l2+b2 = diagonal2=40

Also, lb=20

 

l+b2=l2+b2+2lb = 41 + 40 =81 

(l + b) = 9.

Perimeter = 2(l + b) = 18 cm.

Report Error

View Answer Report Error Discuss

48 35468
Q:

Find the volume (in cm3) of a sphere of diameter 7 cm.

 

A) 140.25 B) 179.67
C) 337.16 D) 213.74
 
Answer & Explanation Answer: B) 179.67

Explanation:
Report Error

View Answer Report Error Discuss

Filed Under: Volume and Surface Area
Exam Prep: Bank Exams

2 35035
Q:

Find the total surface area (in cm2) of a hemisphere of diameter 21 cm.

 

A) 1039.5   B) 844.5  
C) 637   D) 472
 
Answer & Explanation Answer: A) 1039.5  

Explanation:
Report Error

View Answer Report Error Discuss

Filed Under: Volume and Surface Area
Exam Prep: Bank Exams

2 34798