Vital Capacity

Q.

What is the vital capacity of our lungs?

1. Inspiratory reserve volume plus expiratory reserve volume

2. Inspiratory reserve volume plus tidal volume

3. Total lung capacity minus expiratory reserve volume

4. Total lung capacity minus residual volume

Q. After forceful inspiration, the amount of air that can be breathed out by maximum forced expiration is equal to

1. Inspiratory Reserve Volume (IRV) + Expiratory Reserve Volume (ERV)+Tidal Volume (TV)+Residual Volume (RV)
2. IRV+RV+ERV
3. IRV+TV+ERV
4. TV+RV+ERV

Q. Distinguish between vital capacity and total lung capacity.

Q. Listed below are four respiratory capacites (i - iv) and four jumbled respiratory volumes of a normal human adult:

Respiratory capacities	Respiratory volumes
(i) Residual volume	2500 mL
(ii) Vital capacity	3500 mL
(iii) Inspiratory reserve volume	1200 mL
(iv) Inspiratory capacity	4500 mL

Which one of the following is the correct matching of two capacities and volumes?

1. (ii) 2500 mL, (iii) 4500 mL
   
2. (iii) 1200 mL, (iv) 2500 mL
3. (iv) 3500 mL, (i) 1200 mL
4. (i) 4500 mL, (ii) 3500 mL

Q. Ice starts forming in lake with water at $0^{\circ }$ C and when the atmospheric temperature is $-{10}^{\circ }$ C . If the time taken for 1 cm of ice be 7 hours, then the time taken for the thickness of ice to change from 1 cm to 2 cm is

1. 7 hours
2. 14 hours
3. Less than 7 hours
4. More than 7 hours

Q.

One end of a copper rod of length 1.0 m and area of cross-section ${10}^{-3}$ is immersed in boiling water and the other end in ice. If the coefficient of thermal conductivity of copper is $92cal/m-s{-}^{\circ }C$ and the latent heat of ice is $8\times {10}^{4}cal/kg$, then the amount of ice which will melt in one minute is

1. $9.2\times {10}^{-3}kg$

2. $8\times {10}^{-3}kg$

3. $6.9\times {10}^{-3}kg$

4. $5.4\times {10}^{-3}kg$

Q. One mole of an ideal monoatomic gas is kept in a rigid vessel. The vessel is kept inside a chamber whose temperature is ${87}^{\circ }\text{C}$. Initially, the temperature of the gas is $4^{\circ }\text{C}$. The walls of the vessel have an inner surface of area $500{\text{cm}}^2$ and thickness of $2\text{cm}$. If the temperature of the gas increases to $8^{\circ }\text{C}$ in $5.0\text{seconds}$, find the thermal conductivity of the material of the walls.

1. $5\text{W/mK}$
2. $0.05\text{W/mK}$
3. $0.5\text{W/mK}$
4. $50\text{W/mK}$

Q. The figure shows a system of two concentric spheres of radii $r_1$ and $r_2$ and kept at temperatures $T_1$ and $T_2$, respectively. The radial rate of flow of heat in a substance between the two concentric spheres is proportional to

1. $\frac{r_1{r}_2}{(r_1-r_2)}$
2. $(r_2-r_1)$
3. $(r_2-r_1)\left(r_1{r}_2\right)$
4. $In\left(\frac{r_2}{r_1}\right)$

Q. A wall has two layers $A$ and $B$, each made of different material. Both the layers have the same thickness. The thermal conductivity for $A$ is twice that of $B$. Under steady state, the temperature difference across the whole wall is ${36}^{\circ }C$. Then the temperature difference across the layer $A$ is

1. $6^{\circ }C$
2. ${12}^{\circ }C$
3. ${18}^{\circ }C$
4. ${24}^{\circ }C$

Q. The maximum volume of air a person can breathe in after a forced expiration is called ___________.

1. vital capacity
2. total lung capacity
3. functional residual capacity
4. none of the above

Q.

Four rods of identical cross-sectional area and made from the same metal form the sides of square. The temperature of two diagonally opposite points is T and $\sqrt{2}$ T respective in the steady state. Assuming that only heat conduction takes place, what will be the temperature difference between other two points

1. $\frac{\sqrt{2}+1}{2}T$

2. $\frac{2}{\sqrt{2}+1}T$

3. 0

4. None of these

Q. A partition wall has two layers A and B in contact, each made of a different material. They have the same thickness but the thermal conductivity of layer A is twice that of layer B. If the steady state temperature difference across the wall is 60k, then the corresponding difference across the layer A is

1. 10 K
2. 20 K
3. 30 K
4. 40 K

Q. A furnace is made of a red brick wall of thickness $0.5\text{m}$ and conductivity $0.7\text{W/mK}$. For the same rate of heat conduction and the same temperature drop, this can be replaced by a diatomite wall of conductivity $0.14\text{W/mK}$ and the same cross-sectional area. Find the thickness of the diatomite wall.

1. $0.05\text{m}$
2. $0.1\text{m}$
3. $0.2\text{m}$
4. $0.5\text{m}$

Q. A rod of length $L$ and uniform cross-sectional area has varying thermal conductivity which changes linearly from $2K$ at end $B$ to $K$ at the other end $A$. The ends $A$ and $B$ of the rod are maintained at constant temperature ${100}^{\circ }C$ and $0^{\circ }C$, respectively. At steady state, the graph of temperature : $T=T\left(x\right)$ where $x=$ distance from end $A$ will be

1. 
2. 
3. 
4. 

Q. The temperature of the two outer surfaces of a composite slab, consisting of two materials having coefficients of thermal conductivities $K$ and $2K$, and thickness $x$ and $4x$ respectively are $T_2$ and $T_1(T_2>T_1)$ as shown in figure. The cross-sectional area of the slab is $A$. The rate of heat transfer through the slab in steady state is $\left[\frac{A(T_2-T_1)K}{fx}\right]$, where $f$ is equal to

Q.

The maximum volume of air that can be released from the lungs by forceful expiration after deepest inspiration is called the ___.

1. total lung capacity

2. vital capacity

3. tidal volume

4. ventilation rate

Q. Two walls of thickness $d_1$ and $d_2$, thermal conductivities $K_1$ and $K_2$ are in contact. In the steady state, if the temperature at the outer surfaces are $T_1$ and $T_2$, the temperature at the contact of the walls will be

1. $\frac{K_1{T}_1+K_2{T}_2}{d_1+d_2}$
2. $\frac{K_1{T}_1{d}_2+K_2{T}_2{d}_1}{K_1{d}_2+K_2{d}_1}$
3. $\frac{(K_1{d}_1+K_2{d}_2)T_1{T}_2}{T_1+T_2}$
4. $\frac{K_1{d}_1{T}_1+K_2{d}_2{T}_2}{K_1{d}_1+K_2{d}_2}$

Q. If a liquid takes $30\text{s}$ in cooling from ${95}^{\circ }\text{C}$ to ${90}^{\circ }\text{C}$ and $70\text{s}$ in cooling from ${55}^{\circ }\text{C}$ to ${50}^{\circ }\text{C}$ then temperature of room is -

1. ${16.5}^{\circ }\text{C}$
2. ${22.5}^{\circ }\text{C}$
3. ${28.5}^{\circ }\text{C}$
4. ${32.5}^{\circ }\text{C}$

Q.

Two slabs A and B of different materials but of the same thickness are joined as shown in the figure. The thermal conductivities of A and B are $k_1$ and $k_2$ respectively. The thermal conductivity of the composite slab will be

1. $(k_1+k_2)$

2. $\frac{1}{2}(k_1+k_2)$

3. $\sqrt{k_1{k}_2}$

4. $\frac{2k_1{k}_2}{(k_1+k_2)}$

Q.

Which of these is the sum of the other three?

1. Tidal volume

2. Expiratory reserve volume

3. Vital capacity

4. Inspiratory reserve volume

Q. A composite block is made of slabs A, B, C, D and E of different thermal conductivities (given in terms of a constant K) and sizes (given in terms of length. L) as shown in the figure. All slabs are of same with. Heat Q flows only from left to right through the blocks. Then, in steady state

1. heat flown trough A and E slabs are same
2. heat flow through slab e is maximum
3. temperature difference across slab E is smallest
4. heat flow through C = heat flow through B + heat flow through D

Q. Vital capacity (VC) of lungs is_____________________

1. 1500ml
2. 2000ml
3. 2300ml
4. 4300ml

Q. The heat conduction equation $\frac{dQ}{dt}=-kA\left(\frac{dT}{dx}\right)$ applied for heat transfer through a plane slab presumes:
1. Steady- state one-dimensional conduction.
2. Constant value of thermal conductivity
3. The bounding surfaces are isothermal.
4. Temperature gradient is constant.
of these statements:-

1. $1,2,$ and $3$ are correct
2. $2$ and $4$ are correct
3. $2,3,$ and $4$ are correct
4. $1$, $3$ and $4$ are correct

Q. In the figure shown below, two rods are maintained at the same temperature difference between the ends. As a result, heat is flowing through two rods made of the same material. If the diameters of the rods are in the ratio $1:4$ and their lengths are in the ratio $3:2$, then find the ratio of the rates of flow of heat through them.

1. $1:24$
2. $1:8$
3. $1:4$
4. $1:6$

Q. Rate of heat flow is for an object having larger cross-section among the two objects with the same length, temperature difference & material.

1. higher
2. lower
3. same

Q. Two thin metallic spherical shells of radius $a$ and $2a$ are placed with their centers coinciding. A material of thermal conductivity $k$ is filled in the space between them. Determine the expression for thermal resistance of the system.

1. $\frac{1}{8\pi ka}$
2. $\frac{8a^2}{\pi k}$
3. $\frac{1}{4\pi ka}$
4. $\frac{1}{2\pi ka}$

Q. A container of negligible heat capacity contains $1\text{kg}$ water. It is connected by a steel rod of length $1\text{m}$ and area of cross section $1{\text{m}}^2$ to a large steam chamber which is maintained at ${100}^{\circ }\text{C}$. If the initial temperature of water is $0^{\circ }\text{C}$, find the time (in seconds) after which it reaches ${50}^{\circ }\text{C}$ .
[Neglect heat capacity of steel rod and assume no heat is lost to surroundings. Also, take specific heat of water $=S{\text{J/kg}}^{\circ }\text{C}$, conductivity of steel $k_{steel}=k{\text{W/m}}^{\circ }\text{C}]$

1. $\frac{S}{k}\ln 2$
2. $\frac{S}{2k}\ln 2$
3. $\frac{2S}{k}\ln 2$
4. $\frac{2k}{S}\ln 2$

Q. A cylindrical aluminium rod of length 2m is maintained at a temperature difference of 10${}^{\circ }$ Celsius. The radius of the rod is 1 cm. Will it make a difference if it were a steel rod of same dimensions?

1. Yes
2. No

Q. Temperature variation under steady state heat conduction across a composite slab of two materials with thermal conductivities $K_1$ and $K_2$ having same cross sectional area is shown in figure. Choose the correct statement.

1. $K_1>K_2$
2. $K_1=K_2$
3. $K_1=0$
4. $K_1<K_2$

Q. A metal rod AB of length $10x$ has its one end $A$ in ice at $0^{\circ }\text{C}$ and the other end (B) in water at ${100}^{\circ }\text{C}$. If a point P on the rod is maintained at ${400}^{\circ }\text{C}$, then it is found that equal amounts of water and ice, evaporate and melt respectively per unit time. The latent heat of vaporization of water is $540{\text{cal g}}^{-1}$ and the latent heat of fusion of ice is $80{\text{cal g}}^{-1}$. If the point P is at a distance of $\lambda x$ from the end A, find the value of $\lambda$.
(Neglect any heat loss to the surroundings)