Question

40.
The volume of a cube is 64 cm3. Its surface area is
a) 96 cm?
b) 64 cm?
c) 128 cm?
d) 16 cm?​

Answer 1

Answer:

96 cm

Step-by-step explanation:

Volume of cube = 64 cm³

Let each side of cube be x.

According to the question :-

➝ x³ = 64 cm³

➝ x³ = 4³

➝ x = 4 cm

Therefore, length of each side of cube = 4 cm

Now , we have to find out surface area of cube.

➡️Surface area of cube (S.A) = 6a² [ where a is length of each side of cube ]

➝ S.A = 6 × (4)²

➝ S.A = 6 × 16

➝ S.A = 96 cm²

Answer :

The surface area of cube whose volume is 64 cm³ = 96 cm²

Additional-Information :

Volume of cylinder = πr²h

T.S.A of cylinder = 2πrh + 2πr²

Volume of cone = ⅓ πr²h

C.S.A of cone = πrl

T.S.A of cone = πrl + πr²

Volume of cuboid = l × b × h

C.S.A of cuboid = 2(l + b)h

T.S.A of cuboid = 2(lb + bh + lh)

C.S.A of cube = 4a²

T.S.A of cube = 6a²

Volume of cube = a³

Volume of sphere = (4/3)πr³

Surface area of sphere = 4πr²

Volume of hemisphere = ⅔ πr³

C.S.A of hemisphere = 2πr²

T.S.A of hemisphere = 3πr²

Answer 2

Answer:

Let a be the side of the cube.

Then given a

3

=64

or, a=4.

Then its surface area will be 6×a

2

=6×16=96 cm

2

.