1
You visited us
1
times! Enjoying our articles?
Unlock Full Access!
Byju's Answer
Standard VIII
Mathematics
Volume of a Cube
The surface a...
Question
The surface area of a cube increases at the rate of
12
c
m
2
/
s
e
c
. Find the rate at which its volume increases, when its edge has length
5
cm.
Open in App
Solution
S
(Surface area of cube)
=
6
a
2
V
(Vol. of cube)
=
a
3
Now,
d
s
d
t
=
12
a
×
d
a
d
t
=
12
⟹
a
d
a
d
t
=
1
⟹
d
v
d
t
=
3
a
2
d
a
d
t
=
3
a
2
×
1
a
=
3
a
Suggest Corrections
1
Similar questions
Q.
The surface area of a cube is increasing at the rate of
2
c
m
2
/
s
e
c
. When its edge is 90 cm, the volume is increasing at the rate of.
Q.
The volume of a cube is increasing at the rate of
9
c
m
3
/
s
e
c
. How fast is its surface area increasing when the length of an edge is
10
c
m
?
Q.
The volume of a cube is increasing at the rate of
9
c
m
3
/
s
e
c
. How fast is its surface area increasing when the length of an edge is
10
c
m
?
Q.
The volume of a cube is increasing at a rate of 7 cubic cm per second. The rate of change of its surface area when the length of an edge is 12 cm is
Q.
The volume of a cube is increasing at a rate of 7 cubic cm per second. The rate of change of its surface area when the length of an edge is 12 cm is