Physics-
General
Easy
Question
A spherical shell of inner radius 
, temperature 
, outer radius 
and temperature 
conducts heat current radailly. Let r be the distance of any point from the centre of the shell. For 
, temperature T in the shell as a function of r can be expressed as T =
The correct answer is:
Solving “
” can be obtained.
Related Questions to study
physics-
A certain mass of a gas is compressed first adiabatically [curve (a)], and then isothermally [curve (b)]. In both the cases, the initial state of the gas is same If 
is the work done in the first case and 
is the work done in the second case , then
A certain mass of a gas is compressed first adiabatically [curve (a)], and then isothermally [curve (b)]. In both the cases, the initial state of the gas is same If is the work done in the first case and is the work done in the second case , then
physics-General
physics-
A resistance ‘R’ connected to an external battery is put inside an adiabatic cylinder containing an ideal gas as shown. The piston can move along cylinder length without friction and atmospheric pressure is 
. The constant speed ‘v’ by which piston of area of cross-section A should be moved so that temperature of gas do not change is
A resistance ‘R’ connected to an external battery is put inside an adiabatic cylinder containing an ideal gas as shown. The piston can move along cylinder length without friction and atmospheric pressure is . The constant speed ‘v’ by which piston of area of cross-section A should be moved so that temperature of gas do not change is
physics-General
physics-
A curve graph showing the dependence of pressure and absolute temperature is obtained for an ideal gas, as shown for a certain process. In the given process
A curve graph showing the dependence of pressure and absolute temperature is obtained for an ideal gas, as shown for a certain process. In the given process
physics-General
maths-
If 
If
maths-General
chemistry-
In the process of extraction of gold, Roasted gold ore 
[x] and [y] are:
In the process of extraction of gold, Roasted gold ore [x] and [y] are:
chemistry-General
chemistry-
Aqueous solution of 
gives test for both 
and 
but after addition of excess of KCN, solution ceases to give test for . This is due to the formation of
Aqueous solution of gives test for both and but after addition of excess of KCN, solution ceases to give test for . This is due to the formation of
chemistry-General
physics-
A light ray I is incident on a plane mirror M. The mirror is rotated in the direction as shown in the figure by an arrow at frequency 
rps. The light reflected by the mirror is received on the wall W at a distance 10 m from the axis of rotation. When the angle of incidence becomes 
the speed of the spot (a point) on the wall is:
A light ray I is incident on a plane mirror M. The mirror is rotated in the direction as shown in the figure by an arrow at frequency rps. The light reflected by the mirror is received on the wall W at a distance 10 m from the axis of rotation. When the angle of incidence becomes the speed of the spot (a point) on the wall is:
physics-General
physics-
A plano concave lens is placed on a paper on which a flower is drawn. How far above its actual position does the flower appear to be?
A plano concave lens is placed on a paper on which a flower is drawn. How far above its actual position does the flower appear to be?
physics-General
physics-
The figure shows a parallel slab of refractive index 
which is surrounded by media of refractive indices 
and 
. Light is incident on the slab at angle of incidence 
. The time taken by the ray to cross the slab is ' 
if incidence is from ' ' and it is ' 
' if the incidence is from ' '. Then assuming that 
and 
, then value of 
.
The figure shows a parallel slab of refractive index which is surrounded by media of refractive indices and . Light is incident on the slab at angle of incidence . The time taken by the ray to cross the slab is ' if incidence is from ' ' and it is ' ' if the incidence is from ' '. Then assuming that and , then value of .
physics-General
physics-
Two blocks each of mass m lie on a smooth table. They are attached to two other masses as shown in the figure. The pulleys and strings are light. An object O is kept at rest on the table. The sides AB & CD of the two blocks are made reflecting. The acceleration of two images formed in those two reflecting surfaces w.r.t. each other is:
Two blocks each of mass m lie on a smooth table. They are attached to two other masses as shown in the figure. The pulleys and strings are light. An object O is kept at rest on the table. The sides AB & CD of the two blocks are made reflecting. The acceleration of two images formed in those two reflecting surfaces w.r.t. each other is:
physics-General
physics-
In the figure shown, the image of a real object O is formed at point I. AB is the principal axis of the mirror. The mirror must be:
In the figure shown, the image of a real object O is formed at point I. AB is the principal axis of the mirror. The mirror must be:
physics-General
physics-
A transparent cylinder has its right half polished so as to act as a mirror. A paraxial light ray is incident from left, that is parallel to principal axis, exits parallel to the incident ray as shown in the figure. The refractive index n of the material of the cylinder is :
A transparent cylinder has its right half polished so as to act as a mirror. A paraxial light ray is incident from left, that is parallel to principal axis, exits parallel to the incident ray as shown in the figure. The refractive index n of the material of the cylinder is :
physics-General
chemistry-
Which of the following statements are true (or) false -
i) 
and 
are coordination isomers
ii) 
and 
are ionisation isomers
iii) 
and 
are linkage isomers
iv) cis platin exhibits geometrical isomerism
Which of the following statements are true (or) false -
i) and are coordination isomers
ii) and are ionisation isomers
iii) and are linkage isomers
iv) cis platin exhibits geometrical isomerism
chemistry-General
physics-
As shown in the figure the observer 'O' sees the distance AB as infinitely large. If refractive index of liquid is m1 and that of glass is 
As shown in the figure the observer 'O' sees the distance AB as infinitely large. If refractive index of liquid is m1 and that of glass is
physics-General
physics-
In the figure ABC is the cross section of a right angled prism and ACDE is the cross section of a glass slab. The value of so that light incident normally on the face AB does not cross the face AC is (given 
)
In the figure ABC is the cross section of a right angled prism and ACDE is the cross section of a glass slab. The value of so that light incident normally on the face AB does not cross the face AC is (given )
physics-General
