Question 1 : Mercury boils at 367 <img style='object-fit:contain' width=6 height=22 src="https://storage.googleapis.com/teachmint/question_assets/NEET/5ea131691ac76a0b860f9e83"> C.However,mercury thermometers are made such that they can measure temperature are made such that they can measure temperature upto 500 <img style='object-fit:contain' width=6 height=22 src="https://storage.googleapis.com/teachmint/question_assets/NEET/5ea131691ac76a0b860f9e83"> C.This is done by
Question 3 : At NTP water boils at <img style='object-fit:contain' width=38 height=20 src="https://storage.googleapis.com/teachmint/question_assets/NEET/5ea1314f1ac76a0b860f9dc1"> . Deep down the mine, water will boil at a temperature
Question 6 :
The factor not needed to calculate heat lost or gained when there is no change of state is
Question 7 : In the Ingen Hauz s experiment the wax melts up to lengths 10 and <img style='object-fit:contain' width=36 height=20 src="https://storage.googleapis.com/teachmint/question_assets/NEET/5ea1322527ce131ff7c04ddc"> on two identical rods of different materials. The ratio of thermal conductivities of the two material is
Question 9 :
Two solid spheres of the same material have the same radius but one is hollow while the other is solid. Both spheres are heated to same temperature. Then
Question 10 :
A gas undergoes an adiabatic change. Its specific heat in the process is
Question 11 : At some temperature <img style='object-fit:contain' width=12 height=20 src="https://storage.googleapis.com/teachmint/question_assets/NEET/5ea1324427ce131ff7c04eb6"> a bronze pin is a little large to fit into a hole drilled in a steel block. The change in temperature required for an exact fit is minimum when
Question 12 :
On increasing the temperature of a substance gradually, which of the following colours will be noticed by you
Question 13 :
When fluids are heated from the bottom, convection currents are produced because
Question 14 :
If the initial temperatures of metallic sphere and disc, of the same mass, radius and nature are equal, then the ratio of their rate of cooling in same environment will be
Question 15 :
A metallic ball and highly stretched spring are made of the same material and have the same mass. They are heated so that they melt, the latent heat required
Question 18 :
The energy supply being cut-off, an electric heater element cools down to the temperature of its surroundings, but it will not cool further because
Question 19 :
A brass disc fits simply in a hole of a steel plate. The disc from the hole can be loosened if the system
Question 20 :
Mud houses are cooler in summer and warmer in winter because
Question 22 : Three objects coloured black, gray and white can with stand hostile conditions at 2800 <img style='object-fit:contain' width=14 height=22 src="https://storage.googleapis.com/teachmint/question_assets/NEET/5ea131461ac76a0b860f9d6e"> . These objects are thrown into furnace where each of them attains a temperature of 2000 <img style='object-fit:contain' width=18 height=22 src="https://storage.googleapis.com/teachmint/question_assets/NEET/5ea1326c1ac76a0b860fa2c8"> Which object will glow brightest?
Question 26 :
We consider the radiation emitted by the human body. Which of the following statements is true?
Question 27 :
If the ratio of coefficient of thermal conductivity of silver and copper is 10 : 9, then the ratio of the lengths upto which wax will melt in Ingen Hauz experiment will be
Question 28 :
As compared to the person with white skin, the person with black skin will experience
Question 29 :
If the temperature of the sun (black body) is doubled, the rate of energy received on earth will be increased by a factor of
Question 30 :
If the length of a cylinder on heating increases by 2%, the area of its base will increase by
Question 32 : When the pressure on water is increased the boiling temperature of water as compared to <img style='object-fit:contain' width=38 height=20 src="https://storage.googleapis.com/teachmint/question_assets/NEET/5ea1314f1ac76a0b860f9dc1"> will be
Question 33 :
Which of the following is more close to a black body?
Question 34 :
Four rods of silver, copper, brass and wood are of same shape. They are heated together after wrapping a paper on it, the paper will burn first on
Question 35 :
Relation between the colour and the temperature of a star is given by
Question 36 :
In order that the heat flows from one part of a solid to another part, what is required
Question 37 :
Mode of transmission of heat, in which heat is carried by the moving particles, is
Question 38 : One quality of a thermometer is that its heat capacity should be small. If <img style='object-fit:contain' width=9 height=20 src="https://storage.googleapis.com/teachmint/question_assets/NEET/5ea1314d1ac76a0b860f9dab"> is a mercury thermometer, <img style='object-fit:contain' width=10 height=20 src="https://storage.googleapis.com/teachmint/question_assets/NEET/5ea1314d1ac76a0b860f9dac"> is a resistance thermometer and <img style='object-fit:contain' width=10 height=20 src="https://storage.googleapis.com/teachmint/question_assets/NEET/5ea131b71ac76a0b860f9fe5"> thermocouple type then
Question 39 : The mechanical equivalent of heat <img style='object-fit:contain' width=6 height=20 src="https://storage.googleapis.com/teachmint/question_assets/NEET/5ea132901ac76a0b860fa378"> is
Question 40 :
In which mode of transmission, the heat waves travel along straight line with the speed of light?
Question 41 :
The ratio of thermal conductivity of two rods of different material is 5:4. The two rods of same area of cross-section and same thermal resistance will have the lengths in the ratio
Question 43 :
On heating, the temperature at which water has minimum volume is
Question 44 :
Which of the following is the correct device for the detection of thermal radiation
Question 46 :
A piece of blue glass heated to a high temperature and a piece of red glass at room temperature, are taken inside a dimly lit room then
Question 47 :
If mass-energy equivalence is taken into account, when water is cooled to form ice, the mass of water should
Question 48 : Total energy emitted by a perfectly black body is directly proportional to <img style='object-fit:contain' width=19 height=22 src="https://storage.googleapis.com/teachmint/question_assets/NEET/5ea132a427ce131ff7c05104"> where <img style='object-fit:contain' width=9 height=22 src="https://storage.googleapis.com/teachmint/question_assets/NEET/5ea132181ac76a0b860fa16e"> is
Question 50 :
The earth radiates in the infra-red region of the spectrum. The spectrum is correctly given by
Question 51 :
A rod is foxed between two points at 20C the coefficient of linear expansion of material of rod is $1.1{ 10 }^{ -5 }/C$ and Young's modulus is $1.2{ 10 }^{ 11 }N/m^{ 2 }$. Find the stress developed in the rod if temperature of rod becomes $10C$
Question 52 :
An iron wire of length 4 m and diameter 2 mm is loaded with a weight of 8 kg. if the young's modulus 'Y' for iron is $2*10^11 Nm^-2 then the increase in length of the wire is
Question 53 :
Two wires A and B are stretched by the same load. If the area of cross-section of wire 'A' is double that of 'B', then the stress of 'B' is?
Question 54 :
A rod of length L and diameter D is subjected to a tensile load P. Which of the following is sufficient to calculate the resulting change in diameter?
Question 55 : <div>A steel bolt of cross-sectional area $A_b \, = \, 5 \, \times \, 10^{-5} \, m^2$ is passed through a cylindrical tube made of aluminium. Cross-sectional area of the tube material is $A_t \, = \, 10^{-4} \, m^2$ and its length is l = 50 cm. The bolt is just taut so that there is no stress in the bolt and temperature of the assembly increases through $\Delta\theta \, = \, 10^{\circ}C$. Given, coefficient of linear thermal expansion of steel, $\alpha_b \, = \, 10^{-5}/ ^{\circ}C.$ </div><div>Young's modulus of steel $Y_b \, = \, 2 \, \times \, 10^{11} \, N/m^2. $</div><div>Young's modulus of Al, $Y_t \, = \, 10^{11} N/m^2,$ coefficient of </div><div>linear thermal expansion of Al $\alpha_t \, = \, 2 \, \times \, 10^{-5}/^{\circ}C. $</div><div>The tensile stress in bolt is:</div>
Question 56 :
Two Metal strips are riveted together at their ends by four rivets, each of diameter {tex} \alpha = 6 \mathrm { mm } {/tex}. The maximum tension that can be exerted by the riveted strip (if the Shearing stress on the rivet is not to exceed {tex} 6.9 \times 10 ^ { 7 } \mathrm { Pa } {/tex} ) is?
Question 57 :
A metallic wire is subjected to stress and compression periodically with very high stresses. How will the plot of the stress-strain relationship be indicated
Question 58 :
A thin 1 m long rod has a radius of 5 mm.1 A force of 50 $\pi kN$ is applied at one end to determine its Young's modulus. Assume that the force is exactly known. If the least count in the measurement of all lengths is 0.01 mm, which of the following statements is false ? <br>
Question 59 :
If a beam of metal supported at the two ends is loaded at the centre, then the depression at the centre will be proportional to
Question 60 :
The buckling of a beam is found to be more if __________.
Question 61 :
A lift of mass $10^{3}\ kg$ is tied with thick iron wires. If the maximum acceleration of the lift is $1.2\ ms^{-2}$ and the maximum safe stress is $1.4 \times 10^{8}\ Nm^{-2}$, the minimum diameter of wire is ($g=9.8\ ms^{-2}$)
Question 62 :
The bulk modulus of a spherical objects is '$B$'. If it is subjected to uniform pressure '$P$', the fractional decrease in radius is:
Question 63 :
Vessel of $1 \times 10^{-3} m^{3}$volume contains an oi. If a pressure of $1.2 \times 10^{5} N/m^{2}$is applied on it, thenvolume decreases by $0.3\times 10^{-3}m^{3}$ . The bulk modulus of oil is
Question 64 :
What per cent of length of wire increases by applying a stress of {tex}1 \mathrm{kg\ weight/mm^2}{/tex} on it? [{tex}\mathrm Y = 1 \times 10 ^ { 11 } \mathrm { N } / \mathrm { m } ^ { 2 }{/tex} and {tex} 1 \mathrm { kg \ weight}= 9.8{/tex}]
Question 65 :
The length of a wire is $1.0 m$ and the area of cross-section is $1.0 \times 10^{-2} cm^{2}$ . If the work done for increase in length by $0.2 cm$ is $0.4 joule$, then Young's modulus of the material of the wire is<br><br>
Question 66 :
Two wire of same radius and length are subjected to the same load, One wire is of steel and the other is copper. If Young's modulus of steel is twice that of copper, then the ratio of elastic energy stored per unit volume of steel to that of copper wire is
Question 67 : 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<br><img style='object-fit:contain' src="https://storage.googleapis.com/teachmint/question_assets/NEET/5d5fcbc7e5db655bbf10a07a"><br>
Question 68 :
When temperature of a gas is $20^oC$ and pressure is changed from ${ P }_{ 1 }=1.0\times { 10 }^{ 5 } Pa$ to ${ P }_{ 2 }=1.65\times { 10 }^{ 5 } Pa$ and the volume is changed by 10%. The bulk modulus is :
Question 69 :
A wire of cross section $A$ is stretched horizontally between two clamps located $2lm$ apart. A weight $Wkg$ is suspended from the mid-point of the wire.If the Young's modulus of the material is $Y$, the value of extension $x$ is<br>
Question 70 :
A smooth uniform string of natural length <i>l</i>, cross-sectional area A and Young's modulus Y is pulled along its length by a force F on a horizontal surface. Find the elastic potential energy stored in the string.
Question 71 :
A sphere contracts in volume by $0.01$% when taken to the bottom of lake $1km$ deep. If the density of water is $1gm/cc$, the bulk modulus of water is
Question 72 :
A force F is required to break a wire of length l and radius r. What force is required to break a wire, of same material having twice the length and six times the radius?
Question 73 :
A wire of cross section $A$ is stretched horizontally between two clamps located $2l\ m$ apart. A weight $W\ kg$ is suspended from the mid-point of the wire. If the mid-point sags vertically through a distance $x < 1$ the strain produced is<br>
Question 74 :
In a surrounding medium of temperature {tex} 10 ^ { \circ } \mathrm { C } , {/tex} a body takes {tex} \mathrm { 7min } {/tex} for a fall of temperature from {tex} 60 ^ { \circ } \mathrm { C } {/tex} to {tex} 40 ^ { \circ } \mathrm { C } {/tex} . In what time the temperature of the body will fall from {tex} 40 ^ { \circ } \mathrm { C } {/tex} to {tex} 28 ^ { \circ } \mathrm { C } ? {/tex}
Question 75 :
A ball falling in a lake of depth 200 m show 0.1% decrease in its volume at the bottom. What is the bulk modulus of the material of the ball:-
Question 76 :
In $CGS$ system, the Young's modulus of a steel wire is $2 \times 10^{12}$. To double the length of a wire of unit cross section area, the force required is <br><br>
Question 77 : A student takes {tex} \mathrm {50 gm } {/tex} wax {tex} \left. \text { (specific heat = } 0.6 \mathrm { kcal } / \mathrm { kg } ^ { \circ } \mathrm { C } \right) {/tex} and heats it till it boils. The graph between temperature and time is as follows. Heat supplied to the wax per minute and boiling point are respectively<br><img style='object-fit:contain' src="https://data-screenshots.sgp1.digitaloceanspaces.com/5eafce7e96c8e96ecbfdc756.jpg" />
Question 78 :
Assertion: Bulk modulus of elasticity can be defined for all three states of matter, solid liquid and gas,
Reason: Young's modulus is not defined for liquids and gases,
Question 79 :
An air filled balloon is at a depth of $1\ km$ below the water level in an ocean. Determine the normal stress on the balloon<br>(atmospheric pressure $= 10^{5} Pa)$.
Question 80 :
The bulk modulus of water is $2.1 \times 10^9 N/m^2$. The pressure required to increase the density of water by $0.1$% is:-
Question 81 :
The pressure of a medium is changed from $1.01\times 10^{5}\ Pa$ to $1.165\times 10^{5}\ Pa$ and change in volume is $10\%$ keeping temperature constant. The bulk modulus of the medium is
Question 82 :
In a Young's double slit experiment, the intensity at the cetral maximum is $l_{0-}$. The intensity ata distance $\beta/4$ from the central maximum is ($\beta $is frige width)
Question 83 :
Three wires A, B, C made of different materials elongated by 1.5, 2.5, 3.5 mm, under a load of 5kg. If the diameters of the wires are the same,the most elastic material is that of
Question 84 :
The volume change of a solid copper cube $10cm$ on an edge, when subjected to a pressure of $7MPa$ is then<br/>(Bulk modulus of copper $=140GPa$)
Question 85 :
The relation between Young's modulus $Y$, bulk modulus $K$ and modulus of elasticity $\sigma$ is
Question 86 :
The breaking stress of a material is $10^{9}$ pascal. If the density of material is $3\times 10^{3}Kg/m^{3}$. The minimum length of the wire for which it breaks under its own weight will be<br>
Question 87 :
An Indian rubber cord $L$ metre long and area of cross-section $A$ meter$^2$ is suspended vertically. Density of rubber is $\rho \ kg/$ meter$^3$ and Young's modulus of rubber is $Y$ Newton/metre$^2$. If the cord extends by $l$ metre under its own weight, then extension $l$ is:
Question 88 :
A light rod of length $2.00 m$ is suspended from the ceiling horizontally by means of two vertical wires of equal length tied to its ends. One of the wires is made of steel and is of cross section $10^{-3}m^{2}$ and the other is of brass of cross-section $2\times10^{-3}m^{2}$ . Find out the position along the rod at which a weight may be hung to produce.(Youngs modulus for steel is 2x10$^{11}$N /m$^{2}$ and for brass is 10$^{11}$N / m$^{2}$ )<br/>a) equal stress in both wires<br/>b) equal strains on both wires<br/>
Question 89 :
The bulk modulus of water if its volume changes from $100$ litre to $99.5$ litre under pressure of $100atm$ is then<br/>(Take $1\quad atm={ 10 }^{ 5 }N{ m }^{ -2 }\quad $)
Question 90 :
When a $4\ kg$ mass a hung vertically on a light spring that obeys Hooke's law, the spring stretches by $2\ cm$. The work required to be done by an external agent in stretching this spring by $5\ cms$ will be $(g = 9.8\ metres/ sec^{2})$.
Question 91 :
When the tension in a metal wire is $T_{1}$, its length is $l_{1}$. When the tension is $T_{2}$, its length is $l_{2}$. The natural length of wire is
Question 92 :
A ball falling in a lake to a depth $200m$ shows a decrease of $0.1$% in its volume at the bottom. the bulk modulus of the ball is
Question 94 :
A cube is shifted to a depth of $100m$ is alake. The change in volume is $0.1$%. The bulk modules of the material is nearly<br>
Question 95 :
A spherical ball is compressed by $0.01$% when a pressure of $100 $ atmosphere is applied on it. Its bulk modulus of elasticity in $dyne/cm^{2}$ will be approximately<br/>
Question 96 :
Bulk Modulus, Pressure, Force, Stress, which one of these wont have the same unit as the others?
Question 97 :
A steel wire is stretched with a definite load. If the Young's modulus of the wire is $Y$. For decreasing the value of $Y$<br><br>
Question 98 : The top of an insulated cylinder container is covered by a disc having emissivity {tex}0.6{/tex} and conductivity {tex}\mathrm{ 0.167 WK^{-1}\,m^{-1}}{/tex} and thickness {tex}1 \mathrm {cm}{/tex}. The temperature is maintained by circulating oil as shown in figure. Find the radiation loss to the surrounding in {tex} \mathrm { Jm } ^ { - 2 } \mathrm { s } ^ { - 1 } {/tex} if temperature of the upper surface of the disc is {tex} 27 ^ { \circ } \mathrm { C } {/tex} and temperature of the surrounding is {tex} 27 ^ { \circ } \mathrm { C } {/tex} .<br><img style='object-fit:contain' src="https://storage.googleapis.com/teachmint/question_assets/NEET/5d5fcb76d3eb695bc07eb1b4">
Question 99 :
What is the tension in string at A immediately after the string at B breaks?
Question 100 :
The modulus of elasticity of a material does not depend upon<br>
Question 101 :
A plattorm is suspended by four wires at its corners. The wires are {tex} 3 \mathrm { m } {/tex} long and have a diameter of {tex} 2.0 \mathrm { mm } {/tex}. Young's modulus for the material of the wires is {tex} 1,80,000 \mathrm { MPa } {/tex}. How far will the platform drop (due to elongation of the wires) if a {tex} 50 \mathrm { kg } {/tex} load is placed at the centre of the platform?<br>
Question 102 :
Which of the following statements is/are false about mode of heat transfer?
Question 103 :
{tex}10 \mathrm {gm}{/tex} of ice cubes at {tex} 0 ^ { \circ } \mathrm { C } {/tex} are released in a tumbler (water {tex} \text { equivalent } 55 \mathrm { g } ) {/tex} at {tex} 40 ^ { \circ } \mathrm { C } {/tex} . Assuming that negligible heat is taken from the surroundings, the temperature of water in the tumbler becomes nearly {tex} ( \mathrm { L } = 80 \mathrm { cal } / \mathrm { g } ) {/tex}<br>
Question 104 :
In Searle's experiment to find Young's modulus the diameter of wire is measured as $d=0.05cm$, length of wire is $l=125cm$ and when a weight,$m=20.0kg$ is put, extension in wire was found to be $0.100cm$. Find the maximum permissible error in Young's modulus $(Y)$. Use:$Y=\displaystyle\frac{mgl}{(\pi/4)d^2x}$.
Question 105 :
When an elastic material with Young's modulus Y is subjected to stretching stress S, elastic energy stored per unit volume of the material is
Question 106 :
The ratio of the lengths of two rods is $4:3 $ . The ratio of their coefficients of cubical expasion is $ 2:3 $ . Then the ratio of their liner expansions when they are heated through same temperature difference is :
Question 107 :
A rubber ball is brought into 200 m deep water, its volume is decreased by 0.1% then volume  elasticity coefficient of the material of ball will be:<br/>$(Given\ \rho = 10^3 kg/m^3$ and $ g = 9.8 ms^{-2})$
Question 108 :
$\mathrm{A}$ student performs an experiment to determine the Young's modulus of a wire, exactly 2 $\mathrm{m}$ long, by Searle's method. In a particular reading, the student measures the extension in the length of the wire to be $0.8 mm$ with an uncertainty of $\pm 0.05$ mm at a load of exactly $1.0 kg$. The student also measures the diameter of the wire to be $0.4 mm$ with an uncertainty of $\pm 0.01$ mm. Take $\mathrm{g}=9.8\mathrm{m}/\mathrm{s}^{2}$ (exact). The Young's modulus obtained from the reading is <br>
Question 109 :
Two rods of different materials having coefficients of thermal expansion and Young's moduli ${Y}_{1}, {Y}_{2}$, respectively are fixed between two rigid massive walls. The rods are heated such that undergo the same increase in temperature. There is no bending of the rods. If ${\alpha}_{1}:{\alpha}_{2}= 2:3$, the thermal stresses developed in the two rods are equal provided ${Y}_{1}: {Y}_{2}$ is equal to:<br/>
Question 110 :
A glass flask of volume one litre at $0^o$C is filled level full of mercury at this temperature. The flask and mercury are now heated to $100^o$C. How much mercury will spill out, if coefficient of volume expansion of mercury is $1.2\times 10^{-4}/^o$C and linear expansion of glass is $0.1\times 10^{-4}/^o$C, respectively?
Question 111 :
The Young's experiment is performed with the lights of blue $\left( \lambda =4360\mathring { A } \right) $ and green colour $\left( \lambda =5460\mathring { A } \right) ,$ if the distance of the ${ 4 }^{ th }$ fringe from the centre is x, then
Question 112 :
The radiation energy density per unit wavelength at a temperature {tex}\mathrm T{/tex} has a maximum at a wavelength {tex} \lambda _ { 0 } . {/tex} At temperature {tex} 2 \mathrm { T } , {/tex} it will have a maximum wavelength
Question 113 :
On observing light from three different stars {tex} \mathrm { P } , \mathrm { Q } {/tex} and {tex} \mathrm { R } {/tex} , it was found that intensity of violet colour is maximum in the spectrum of {tex} \mathrm { P } {/tex} , the intensity of green colour is maximum in the spectrum of {tex} \mathrm { R } {/tex} and the intensity of red colour is maximum in the spectrum of {tex} \mathrm { Q } {/tex}. If {tex} \mathrm T_{ \mathrm P},\, \mathrm T _ { \mathrm Q } {/tex} and {tex} \mathrm T _ { \mathrm R } {/tex} are the respective absolute temperature of {tex} \mathrm{P , Q} {/tex} and {tex} \mathrm R , {/tex} then it can be concluded from the above observations that
Question 114 :
The sprinkling of water slightly reduces the temperature of a closed room because
Question 115 :
Two rods of same length and area of cross-section {tex} \mathrm { A } _ { 1 } {/tex} and {tex} \mathrm { A } _ { 2 } {/tex} have their ends at the same temperature. If {tex} \mathrm { K } _ { 1 } {/tex} and {tex} \mathrm { K } _ { 2 } {/tex} are their thermal conductivities, {tex} \mathrm c _ { 1 } {/tex} and {tex} \mathrm c _ { 2 } {/tex} are their specific heats and {tex} \mathrm d _ { 1 } {/tex} and {tex} \mathrm d _ { 2 } {/tex} are their densities, then the rate of flow of heat is the same in both the rods if<br>
Question 116 :
An Aluminium and Copper wire of same cross sectional area but having lengths in the ratio $2 : 3$ are joined end to end. This composite wire is hung from a rigid support and a load is suspended from the free end. If the increase in length of the composite wire is $2.1 \ mm$, the increase in lengths of Aluminium and Copper wires are : [$\displaystyle { Y }_{ Al }=20\times { 10 }^{ 11 }{ N }/{ { m }^{ 2 } }$ and $\displaystyle { Y }_{ Cu }=12\times { 10 }^{ 11 }{ N }/{ { m }^{ 2 } }$]
Question 117 :
A body of mass {tex} 10 \mathrm { kg } {/tex} is attached to a wire of radius {tex} 3 \mathrm { cm } {/tex}. It's breaking stress is {tex} 4.8 \times 10 ^ { 7 } \mathrm { Nm } ^ { -2 } {/tex} , the area of cross-section of the wire is {tex} 10 ^ { - 6 } \mathrm { m } ^ { 2 } {/tex}. What is the maximum angular velocity with which it can be rotated in the horizontal circle?
Question 118 :
If a rubber ball is taken down to a 100 m deep lake, its volume decreases by 0.1%. If $g=10\quad m/{ s }^{ 2 }$ then the bulk modulus of elasticity for rubber, in N/${ m }^{ 2 }$, is 
Question 119 :
In a Young's double slit experiment with sodium light, slits are 0.589 m apart. The angular separation of the maximum from the central maximum will be (given $\lambda =589$nm,):
Question 120 : The plots of intensity versus wavelength for three black bodies at temperatures {tex} T _ { 1 } , T _ { 2 } {/tex} and {tex} T _ { 3 } {/tex} respectively are as shown. Their temperature are such that<br><img style='object-fit:contain' src="https://storage.googleapis.com/teachmint/question_assets/NEET/5d5fcb49d3eb695bc07eb18e">
Question 121 :
Take, bulk modulus of water $B = 2100\ MPa$.<br/>What increase in pressure is required to decrease the volume of $200\ litres$ of water by $0.004$ percent?
Question 122 :
Two wires are made of the same material and have the same volume. However wire {tex}1{/tex} has cross- sectional area {tex} A {/tex} and wire {tex}2{/tex} has cross-sectional area {tex} 9 A . {/tex} If the length of wire {tex}1{/tex} increases by {tex} \Delta x {/tex} on applying force {tex} F , {/tex} how much force is needed to stretch wire {tex}2{/tex} by the same amount?
Question 123 :
Two wires of different material and radius have their length in ratio of $1:2.$ if these were stretched by the same force$,$ the strain produced will be in the ratio$.$  
Question 124 :
A black body has maximum wavelength {tex} \lambda _ { m } {/tex} at temperature 2000{tex} \mathrm { K } {/tex} . Its corresponding wavelength at temperature 3000 {tex} \mathrm { K } {/tex} will be
Question 125 : Two rods of same length and transfer a given amount of heat 12 second, when they are joined as shown in figure<br> (i). But when they are joined as shown in figure<br>(ii), then they will transfer same heat in same conditions in<br><img style='object-fit:contain' src="https://storage.googleapis.com/teachmint/question_assets/NEET/5d5fcb8de5db655bbf10a034">
Question 126 :
Two wires are made of the same material and have the same volume. However first wire has crosssectional area {tex} A {/tex} and second wire has crosssectional area {tex} 3 A {/tex}. If the length of first wire increases by {tex} \Delta l {/tex} on applying force {tex} F, {/tex} how much force is needed to stretch second wire by the same amount?
Question 127 :
The length of elastic string, obeying Hooke's law is {tex} \ell _ { 1 } {/tex} metres when the tension {tex} 4 \mathrm { N } {/tex} and {tex} \ell _ { 2 } {/tex} metres when the tension is {tex} 5 \mathrm { N } {/tex}. The length in metres when the tension is {tex} 9 \mathrm { N } {/tex} is -
Question 128 :
A metallic rod {tex} \ell \mathrm { cm } {/tex} long, {tex} \mathrm { A } {/tex} square {tex} \mathrm { cm } {/tex} in cross-section is heated through {tex} \mathrm { t } ^ { \circ } \mathrm { C } {/tex} . If Young's modulus of elasticity of the metal is {tex} \mathrm { E } {/tex} and the mean coefficient of linear expansion is {tex} \alpha {/tex} per degree celsius, then the compressional force required to prevent the rod from expanding along its length is<br>
Question 129 :
Two wires are made of the same material and have the same volume. However wire $1$ has cross-sectional area $A$ and wire $2$ has cross-sectional area $3A$. If the length of wire $1$ increases by $\triangle x$ on applying force $F$, how much force is needed to stretch wire $2$ by the same amount?
Question 130 :
In performing an experiment to determine the Young's modulus Y of steel, a student can record the following values:<br>length of wire l$=(\ell_{0}\pm\Delta$l$){m}$<br>diameter of wire ${d}=({d}_{0}\pm\Delta {d})$ mm<br>force applied to wire ${F}$=$({F}_{0}\pm\Delta {F}){N}$<br>extension of wire ${e}=({e}_{0}\neq\Delta {e})$ mm<br>In order to obtain more reliable value for Y, the followlng three techniques are suggested. <br>Technique (i) A shorter wire ls to be used.<br>Technique (ii) The diameter shall be measured at several places with a micrometer screw gauge.<br>Technique (iii) Two wires are made irom the same ntaterial and of same length. One is loaded at a fixed weight and acts as a reference for the extension of the other which is load- tested<br>Which of the above techniques is/are useful?<br>
Question 131 :
$32 g$ of $O_{2}$ is contained in a  cubical container  of side $1 m$  and  maintained at a temperature of $127 ^{0} C$. The isothermal bulk modulus of elasticity of the gas in terms of universal gas constant $R$ is
Question 132 :
The density of water at {tex} 20 ^ { \circ } \mathrm { C } {/tex} is 998{tex} \mathrm { kg } / \mathrm { m } ^ { 3 } {/tex} and at {tex} 40 ^ { \circ } \mathrm { C } \ 992 {/tex} {tex} \mathrm { kg } / \mathrm { m } ^ { 3 } . {/tex} The coefficient of volume expansion of water is
Question 133 :
Two persons pull a rope towards themselves. Each person exerts a force of {tex} 100 \mathrm { N } {/tex} on the rope. Find the Young's modulus of the material of the rope if it extends in length by {tex} 1 \mathrm { cm } {/tex}. Original length of the rope {tex} = 2 \mathrm { m } {/tex} and the area of cross-section {tex} = 2 \mathrm { cm } ^ { 2 } . {/tex}
Question 135 :
A thin uniform film of refractive index $1.75$ is placed on a sheet of glass of refractive index $1.5$. At room temperature $(20^{\circ}C)$, this film is just thick enough for light with wavelength $600nm$ reflected off the top of the film to be canceled by light reflected from the top of the glass. After the glass is placed in an oven and slowly heated to $170{|circ}C)$, the film concels reflected light wavelength $606nm$. The coefficient of linear expansion of the film is (Ignore any changes in the refractive index of the film due to the temperature change.)
Question 136 :
Two wires {tex} \mathrm A {/tex} and {tex}\mathrm B {/tex} of same material and of equal length with the radii in the ratio {tex}1 : 2{/tex} are subjected to identical loads. If the length of {tex} \mathrm A {/tex} increases by {tex} 8 \mathrm { mm } , {/tex} then the increase in length of {tex} \mathrm { B } {/tex} is
Question 137 :
A body of mass {tex} \mathrm { 5kg } {/tex} falls from a height of {tex}20{/tex} metres on the ground and it rebounds to a height of {tex} 0.2 \mathrm { m } . {/tex} If the loss in potential energy is used up by the body, then what will be the temperature rise? <br>(specific heat of material = {tex}\mathrm{0.09\,cal\,gm^{-1} {^\circ} C ^{-1}}{/tex})<br>
Question 138 :
Temperature of a gas is $20^{0}\mathrm{C}$ and pressure is changed from $1.01\times 10^{5}$ Pa to $1.165\times 10^5\mathrm{P}\mathrm{a}$. If volume is decreased isothermally by 10%. The bulk modulus of gas is (in $Pa$):<br/><br/>
Question 139 :
Consider a compound slab consisting of two different conductivities <b>K</b> and <b>2K</b>, respectively. The equivalent thermal conductivity of the slab is<br>
Question 140 :
A clock which keeps correct time at $20^{\circ}C$, is subjected to $40^{\circ}C$. If coefficient of linear expansion of the pendulum is $12\times 10^{-6}/ ^{\circ}C$, then how much will it gain or loss in time?
Question 141 :
A piece of ice falls from a height h so that it melts completely. Only one-quarter of the heat produced is absorbed by the ice and all energy of ice gets converted into heat during its fall. The value of h is: {tex} \left. \text { [Latent heat of ice is } 3.4 \times 10 ^ { 5 } \mathrm { J } / \mathrm { kg } = 10 \mathrm { N } / \mathrm { kg } \right] {/tex}<br>
Question 142 :
A metal ball immersed in alcohol weighs {tex} \mathrm { W } _ { 1 } {/tex} at {tex} 0 ^ { \circ } \mathrm { C } {/tex} and {tex} \mathrm { W } _ { 2 } {/tex} at {tex} 50 ^ { \circ } \mathrm { C } . {/tex} The coefficient of cubical expansion of the metal is less than that of alcohol. Assuming that the density of the metal is large compared to that of alcohol, it can be shown that<br>
Question 143 :
The coefficient of thermal conductivity of copper, mercury and glass are respectively {tex} \mathrm { K } _ { \mathrm { c } } , \mathrm { K } _ { \mathrm { m } } {/tex} and {tex} \mathrm { K } _ { \mathrm { g } } {/tex} such that {tex} \mathrm { K } _ { \mathrm { c } } > \mathrm { K } _ { \mathrm { m } } {/tex}{tex} > \mathrm { K } _ { \mathrm { g } } . {/tex} If the same quantity of heat is to flow per sec per unit area of each and corresponding temperature gradients are {tex} \mathrm { X } _ { \mathrm { c } } , \mathrm { X } _ { \mathrm { m } } {/tex} and {tex} \mathrm { X } _ { \mathrm { g } } {/tex} then<br>
Question 144 :
The specific heat capacity of a metal at low temperature (T) is given as {tex} C _ { p } \left( k J K ^ { - 1 } \mathrm { kg } ^ { - 1 } \right) = 32 \left( \frac { T } { 400 } \right) ^ { 3 } {/tex}. A {tex}100{/tex} gram vessel of this metal is to be cooled from {tex} 20 ^ { \circ } \mathrm { K } {/tex} to {tex} 4 ^ { \circ } \mathrm { K } {/tex} by a special refrigerator operating at room temperature {tex} \left( 27 ^ { \circ } \mathrm { C } \right) . {/tex} The amount of work required to cool the vessel is
Question 146 :
When the temperature of a rod increases from {tex}\mathrm t{/tex} to {tex} \mathrm { t } + \Delta \mathrm { t } {/tex} , its moment of inertia increases from {tex}\mathrm I{/tex} to {tex} \mathrm { I } + \Delta \mathrm { I } {/tex} . If {tex} \alpha {/tex} be the coefficient of linear expansion of the rod, then the value of {tex} \frac { \Delta \mathrm { I } } { \mathrm { I } } {/tex} is<br>
Question 147 :
A solid cube and a solid sphere of the same material have equal surface area. Both are at the same temperture {tex} 120 ^ { \circ } \mathrm { C } {/tex} , then
Question 148 :
A uniformly tapering conical wire is made from a material of Young's modulus {tex}\mathrm Y{/tex} and has a normal, unextended length {tex}\mathrm L{/tex} . The radii, at the upper and lower ends of this conical wire, have values {tex}\mathrm R{/tex} and {tex} 3 \mathrm { R } , {/tex} respectively. The upper end of the wire is fixed to a rigid support and a mass {tex} \mathrm { M } {/tex} is suspended from its lower end. The equilibrium extended length, of this wire, would equal: {tex} \quad {/tex}
Question 149 :
Which of the following will expand the most for same rise in temperature?
Question 150 :
Two straight metallic strips each of thickness {tex}t{/tex} and length {tex} \ell {/tex} are rivetted together. Their coefficients of linear expansions are {tex} \alpha _ { 1 } {/tex} and {tex} \alpha _ { 2 } {/tex} . If they are heated through temperature {tex} \Delta \mathrm { T } {/tex} , the bimetallic strip will bend to form an arc of radius<br>
