Physics-

General

Easy

Question

# In a vertical U-tube containing a liquid, the two arms are maintained at different temperatures and The liquid columns in the two arms have heights and respectively. The coefficient of volume expansion of the liquid is equal to

## The correct answer is:

### Suppose, height of liquid in each arm before rising the temperature is .

With temperature rise height of liquid in each arm increases

Also

### Related Questions to study

physics-

### A bimetallic strip consists of metals and . It is mounted rigidly at the base as shown. The metal has a higher coefficient of expansion compared to that for metal . when bimetallic strip is placed in a cold bath

The metal X has a higher coefficient of expansion compared to that for metal Y so, on placing bimetallic strip in a cold bath, X will shrink more than . Hence, the strip will bend towards the left.

### A bimetallic strip consists of metals and . It is mounted rigidly at the base as shown. The metal has a higher coefficient of expansion compared to that for metal . when bimetallic strip is placed in a cold bath

physics-General

The metal X has a higher coefficient of expansion compared to that for metal Y so, on placing bimetallic strip in a cold bath, X will shrink more than . Hence, the strip will bend towards the left.

physics-

### The temperature of the two outer surfaces of a composite slab, consisting of two materials having coefficients of thermal conductivity and 2 and thickness and 4, respectively are and . The rate of heat transfer through the slab, in a steady state is , with equals to

Let the temperature of common interface be . Rate of heat flow

=

And =

In steady state, the rate of heat flow should be same in whole system

=

(i)

Hence, heat flow from composite slab is

= (ii)

Accordingly, (iii)

By comparing Eqs. (ii) and (iii), we get

=

And =

In steady state, the rate of heat flow should be same in whole system

=

(i)

Hence, heat flow from composite slab is

= (ii)

Accordingly, (iii)

By comparing Eqs. (ii) and (iii), we get

### The temperature of the two outer surfaces of a composite slab, consisting of two materials having coefficients of thermal conductivity and 2 and thickness and 4, respectively are and . The rate of heat transfer through the slab, in a steady state is , with equals to

physics-General

Let the temperature of common interface be . Rate of heat flow

=

And =

In steady state, the rate of heat flow should be same in whole system

=

(i)

Hence, heat flow from composite slab is

= (ii)

Accordingly, (iii)

By comparing Eqs. (ii) and (iii), we get

=

And =

In steady state, the rate of heat flow should be same in whole system

=

(i)

Hence, heat flow from composite slab is

= (ii)

Accordingly, (iii)

By comparing Eqs. (ii) and (iii), we get

physics-

### A solid material is supplied with heat at constant rate and the temperature of the material changes as shown. From the graph, the false conclusion drawn is

### A solid material is supplied with heat at constant rate and the temperature of the material changes as shown. From the graph, the false conclusion drawn is

physics-General

physics-

### The energy distribution with the wavelength for the black body radiation at temperature is shown in the figure. As the temperature is increased the maxima will

According to Wien’s displacement law . Hence, it temperature increases decreases peak of the curve shift towards left

### The energy distribution with the wavelength for the black body radiation at temperature is shown in the figure. As the temperature is increased the maxima will

physics-General

According to Wien’s displacement law . Hence, it temperature increases decreases peak of the curve shift towards left

physics-

### A metal rod of length has cross sectional areas and as shown in figure. The ends are maintained at temperatures and . The temperature at middle point is

Let be temperature of middle point and in series rate of heat flow is same

### A metal rod of length has cross sectional areas and as shown in figure. The ends are maintained at temperatures and . The temperature at middle point is

physics-General

Let be temperature of middle point and in series rate of heat flow is same

physics-

### The coefficient of thermal conductivity of copper is nine times that of steel. In the composite cylindrical bar show in figure, what will be the temperature at the junction of copper ad steel?

Let the temperature of junction be

3

12

3

12

### The coefficient of thermal conductivity of copper is nine times that of steel. In the composite cylindrical bar show in figure, what will be the temperature at the junction of copper ad steel?

physics-General

Let the temperature of junction be

3

12

3

12

Maths-

### Which function is shown in graph?

### Which function is shown in graph?

Maths-General

Maths-

### Which function is shown in graph?

### Which function is shown in graph?

Maths-General

Maths-

### Which function is shown in graph?

### Which function is shown in graph?

Maths-General

physics-

### Five rods of same dimensions are arranged as shown in figure. They have thermal conductivities When points are maintained at different temperature, no heat would flow through central rod, if

The equivalent electrical circuit, figure in these cases is of Wheatstone bridge. No current would flow through central rod when the bridge is balanced. The condition for balanced Wheatstone bridge is (in terms of resistances)

or

Or

or

Or

### Five rods of same dimensions are arranged as shown in figure. They have thermal conductivities When points are maintained at different temperature, no heat would flow through central rod, if

physics-General

The equivalent electrical circuit, figure in these cases is of Wheatstone bridge. No current would flow through central rod when the bridge is balanced. The condition for balanced Wheatstone bridge is (in terms of resistances)

or

Or

or

Or

physics-

### If two metallic plates of equal thicknesses and thermal conductivities and are put together face to face and a common plate is constructed, then the equivalent thermal conductivity of this plate will be

In series,

### If two metallic plates of equal thicknesses and thermal conductivities and are put together face to face and a common plate is constructed, then the equivalent thermal conductivity of this plate will be

physics-General

In series,

physics-

### The graph, shown in the adjacent diagram, represents the variation of temperature of two bodies, and having same surface area, with time () due to the emission of radiation. Find the correct relation between the emissivity and absorptivity power of the two bodies.

Rate of cooling emissivity(e)

From the graph,

Further emissivity () absorptive power () (good absorbers are good emitters also)

From the graph,

Further emissivity () absorptive power () (good absorbers are good emitters also)

### The graph, shown in the adjacent diagram, represents the variation of temperature of two bodies, and having same surface area, with time () due to the emission of radiation. Find the correct relation between the emissivity and absorptivity power of the two bodies.

physics-General

Rate of cooling emissivity(e)

From the graph,

Further emissivity () absorptive power () (good absorbers are good emitters also)

From the graph,

Further emissivity () absorptive power () (good absorbers are good emitters also)

maths-

Apply SinC+SinD formula

maths-General

Apply SinC+SinD formula

maths-

### Value of is

### Value of is

maths-General

Maths-

### What is for two mutually exclusive sets A and B?

### What is for two mutually exclusive sets A and B?

Maths-General