Question 1: Palette 1/85

NEET 2026 MCQ

$ \text { Match List I with List II: } $

$ \text { List I } $		$ \text { List I I} $
A.	Young's Modulus	I.	$ \frac{\Delta d}{\Delta L}\left(\frac{L}{d}\right) $
B.	Compressibility	II.	$ \frac{F L}{A(\Delta L)} $
C.	Bulk Modulus	III.	$ -\frac{1}{\Delta P}\left(\frac{\Delta V}{V}\right) $
D.	Poisson's Ratio	IV.	$ -P\left(\frac{V}{\Delta V}\right) $

Choose the correct answer from the options given below:

A

A-IV, B-I, C-II, D-III

B

A-III, B-II, C-I, D-IV

C

A-I, B-IV, C-III, D-II

D

A-II, B-III, C-IV, D-I

Question 2: Palette 2/85

NEET 2026 MCQ

A submarine is designed to withstand an absolute pressure of 100 atm . How deep can it go below the water surface?

(Consider the density of water $=1000 \mathrm{~kg} \mathrm{~m}^{-3}$, $1 \mathrm{~atm}=1 \times 10^5 \mathrm{~Pa}$ and gravitational acceleration $g=10 \mathrm{~m} / \mathrm{s}^2$ )

A

990 m

B

9900 m

C

99 m

D

9000 m

Question 3: Palette 3/85

NEET 2026 MCQ

Water flows in a streamline motion through a horizontal pipe of circular cross-section as shown in the figure. The pressure difference of water between $P$ and $Q$ is $15 \mathrm{Nm}^{-2}$. The area of cross-section at $P$ and $Q$ are $40 \mathrm{~cm}^2$ and $20 \mathrm{~cm}^2$, respectively. The rate of flow of water through the pipe, in $\mathrm{cm}^3 \mathrm{~s}^{-1}$, is:

[Take density of water $=1000 \mathrm{~kg} \mathrm{~m}^{-3}$ ]

A

400

B

100

C

200

D

300

Question 4: Palette 4/85

NEET 2026 MCQ

In the measurement of viscosity of liquids using terminal velocity experiment, spherical balls of same radius but having different densities are used. The variation of the terminal velocity ( $v$ ) with the ratio of density of spherical ball ( $\sigma$ ) to density of the liquid ( $\rho$ ), is best represented by:

A

B

C

D

Question 5: Palette 5/85

NEET 2025 MCQ

Consider a water tank shown in the figure. It has one wall at $x=L$ and can be taken to be very wide in the $z$ direction. When filled with a liquid of surface tension $S$ and density $\rho$, the liquid surface makes angle $\theta_0\left(\theta_0 \ll 1\right)$ with the $x$-axis at $x=L$. If $y(x)$ is the height of the surface then the equation for $y(x)$ is:

(take $\theta(x)=\sin \theta(x)=\tan \theta(x)=\frac{d y}{d x}, g$ is the acceleration due to gravity)

A

$\frac{d^2 y}{d x^2}=\sqrt{\frac{\rho g}{s}}$

B

$\frac{d y}{d x}=\sqrt{\frac{\rho g}{s}} x$

C

$\frac{d^2 y}{d x^2}=\frac{\rho g}{s} x$

D

$\frac{d^2 y}{d x^2}=\frac{\rho g}{s} y$

Question 6: Palette 6/85

NEET 2024 MCQ

An ideal fluid is flowing in a non-uniform cross-sectional tube $X Y$ (as shown in the figure) from end $X$ to end $Y$. If $K_1$ and $K_2$ are the kinetic energy per unit volume of the fluid at $X$ and $Y$ respectively, then the correct option is :

A

$K_1=K_2$

B

$2 K_1=K_2$

C

$K_1>K_2$

D

$K_1 < K_2$

Question 7: Palette 7/85

NEET 2024 MCQ

The maximum elongation of a steel wire of $1 \mathrm{~m}$ length if the elastic limit of steel and its Young's modulus, respectively, are $8 \times 10^8 \mathrm{~N} \mathrm{~m}^{-2}$ and $2 \times 10^{11} \mathrm{~N} \mathrm{~m}^{-2}$, is:

A

4 mm

B

0.4 mm

C

40 mm

D

8 mm

Question 8: Palette 8/85

NEET 2024 MCQ

A thin flat circular disc of radius $4.5 \mathrm{~cm}$ is placed gently over the surface of water. If surface tension of water is $0.07 \mathrm{~N} \mathrm{~m}^{-1}$, then the excess force required to take it away from the surface is

A

19.8 mN

B

198 N

C

1.98 mN

D

99 N

Question 9: Palette 9/85

NEET 2024 MCQ

A metallic bar of Young's modulus, $0.5 \times 10^{11} \mathrm{~N} \mathrm{~m}^{-2}$ and coefficient of linear thermal expansion $10^{-5}{ }^{\circ} \mathrm{C}^{-1}$, length $1 \mathrm{~m}$ and area of cross-section $10^{-3} \mathrm{~m}^2$ is heated from $0^{\circ} \mathrm{C}$ to $100^{\circ} \mathrm{C}$ without expansion or bending. The compressive force developed in it is :

A

$5 \times 10^3 \mathrm{~N}$

B

$50 \times 10^3 \mathrm{~N}$

C

$100 \times 10^3 \mathrm{~N}$

D

$2 \times 10^3 \mathrm{~N}$

Question 10: Palette 10/85

NEET 2023 MCQ

The amount of elastic potential energy per unit volume (in SI unit) of a steel wire of length $100 \mathrm{~cm}$ to stretch it by $1 \mathrm{~mm}$ is (if Young's modulus of the wire $=2.0 \times 10^{11} \mathrm{Nm}^{-2}$ ) :

A

$10^{11}$

B

$10^{17}$

C

$10^7$

D

$10^5$

Question 11: Palette 11/85

NEET 2023 MCQ

Which of the following statement is not true?

A

Coefficient of viscosity is a scalar quantity

B

Surface tension is a scalar quantity

C

Pressure is a vector quantity

D

Relative density is a scalar quantity

Question 12: Palette 12/85

NEET 2023 MCQ

The viscous drag acting on a metal sphere of diameter $1 \mathrm{~mm}$, falling through a fluid of viscosity $0.8 \mathrm{~Pa}$ s with a velocity of $2 \mathrm{~m} \mathrm{~s}^{-1}$ is equal to :

A

$15 \times 10^{-3} \mathrm{~N}$

B

$30 \times 10^{-3} \mathrm{~N}$

C

$1.5 \times 10^{-3} \mathrm{~N}$

D

$20 \times 10^{-3} \mathrm{~N}$

Question 13: Palette 13/85

NEET 2023 MCQ

The amount of energy required to form a soap bubble of radius $2 \mathrm{~cm}$ from a soap solution is nearly: (surface tension of soap solution $=0.03 \mathrm{~N} \mathrm{~m}^{-1}$ )

A

$5.06 \times 10^{-4} \mathrm{~J}$

B

$3.01 \times 10^{-4} \mathrm{~J}$

C

$50.1 \times 10^{-4} \mathrm{~J}$

D

$30.16 \times 10^{-4} \mathrm{~J}$

Question 14: Palette 14/85

NEET 2023 MCQ

The venturi-meter works on :

A

Bernoulli's principle

B

The principle of parallel axes

C

The principle of perpendicular axes

D

Huygen's principle

Question 15: Palette 15/85

NEET 2023 MCQ

Let a wire be suspended from the ceiling (rigid support) and stretched by a weight $W$ attached at its free end. The longitudinal stress at any point of cross-sectional area $A$ of the wire is :

A

$W / A$

B

$W / 2 A$

C

Zero

D

$2 W / A$

Question 16: Palette 16/85

NEET 2022 MCQ

Two copper vessels A and B have the same base area but of different shapes. A takes twice the volume of water as that B requires to fill upto a particular common height. Then the correct statement among the following is :

A

Vessel B weighs twice that of A.

B

Pressure on the base area of vessels A and B is same.

C

Pressure on the base area of vessels A and B is not same.

D

Both vessels A and B weigh the same.

Question 17: Palette 17/85

NEET 2022 MCQ

The terminal velocity of a copper ball of radius 5 mm falling through a tank of oil at room temperature is 10 cm s^$-$1. If the viscosity of oil at room temperature is 0.9 kg m^$-$1 s^$-$1, the viscous drag force is :

A

4.23 $\times$ 10^$-$6 N

B

8.48 $\times$ 10^$-$3 N

C

8.48 $\times$ 10^$-$5 N

D

4.23 $\times$ 10^$-$3 N

Question 18: Palette 18/85

NEET 2022 MCQ

A spherical ball is dropped in a long column of a highly viscous liquid. The curve in the graph shown, which represents the speed of the ball (v) as a function of time (t) is

A

A

B

B

C

C

D

D

Question 19: Palette 19/85

NEET 2022 MCQ

If a soap bubble expands, the pressure inside the bubble

A

Decreases

B

Increases

C

Remains the same

D

Is equal to the atmospheric pressure

Question 20: Palette 20/85

NEET 2022 MCQ

Given below are two statements : One is labelled as Assertion (A) and the other is labelled as Reason (R).

Assertion (A) : The stretching of a spring is determined by the shear modulus of the material of the spring.

Reason (R) : A coil spring of copper has more tensile strength than a steel spring of same dimensions.

In the light of the above statements, choose the most appropriate answer from the options given below:

A

Both (A) and (R) are true and (R) is the correct explanation of (A)

B

Both (A) and (R) are true and (R) is not the correct explanation of (A)

C

(A) is true but (R) is false

D

(A) is false but (R) is true

Question 21: Palette 21/85

NEET 2021 MCQ

The velocity of a small ball of mass M and density d, when dropped in a container filled with glycerin becomes constant after some time. If the density of glycerin is ${d \over 2}$, then the viscous force acting on the ball will be :

A

2Mg

B

${{Mg} \over 2}$

C

Mg

D

${{3} \over 2}$Mg

Question 22: Palette 22/85

NEET 2020 MCQ

A capillary tube of radius r is immersed in water and water rises in it to a height h. The mass of the water in the capillary is 5 g. Another capillary tube of radius 2r is immersed in Water. The mass of water that will rise in this tube is :

A

5.0 g

B

10.0 g

C

20.0 g

D

2.5 g

Question 23: Palette 23/85

NEET 2020 MCQ

A wire of length L, are of cross section A is hanging from a fixed support. The length of the wire changed to L₁ when mass M is suspended from its free end. The expression for Young's modulus is :

A

${{Mg\left( {{L_1} - L} \right)} \over {AL}}$

B

${{MgL} \over {A{L_1}}}$

C

${{MgL} \over {A\left( {{L_1} - L} \right)}}$

D

${{Mg{L_1}} \over {AL}}$

Question 24: Palette 24/85

NEET 2019 MCQ

A copper rod of 88 cm and an aluminium rod of unknown length have their increase in length independent of increase in tmperature. The length of aluminium rod is : ($\alpha $_Cu = 1.7 × 10^–5 K^–1 and $\alpha $_Al = 2.2 × 10^–5 K^–1)

A

119.9 cm

B

88 cm

C

68 cm

D

6.8 cm

Question 25: Palette 25/85

NEET 2019 MCQ

The unit of thermal conductivity is :

A

J m^–1 K^–1

B

W m K^–1

C

J m K^–1

D

W m^–1 K^–1

Question 26: Palette 26/85

NEET 2019 MCQ

A soap bubble, having radius of 1 mm, is blown from a detergent solution having a surface tension of 2.5 $ \times $ 10^–2 N/m. The pressure inside the bubble equals at a point Z₀ below the free surface of water in a container. Taking g = 10 m/s², density of water = 10³ kg/m³, the value of Z₀ is :

A

1 cm

B

10 cm

C

100 cm

D

0.5 cm

Question 27: Palette 27/85

NEET 2019 MCQ

When a block of mass M is suspended by a long wire of length L, the length of the wire becomes (L + $l$). The elastic potential energy stored in the extended wire is :

A

Mgl

B

mgL

C

${1 \over 2}$Mgl

D

${1 \over 2}$MgL

Question 28: Palette 28/85

NEET 2019 MCQ

A small hole of area of cross-section 2 mm² present near the bottom of a fully filled open tank of height 2 m. Taking g = 10 m/s², the rate of flow of water through the open hole would be nearly :

A

8.9 × 10^–6 m³/s

B

2.23 × 10^–6 m³/s

C

6.4 × 10^–6 m³/s

D

12.6 × 10^–6 m³/s

Question 29: Palette 29/85

NEET 2018 MCQ

A small sphere of radius ‘r’ falls from rest in a viscous liquid. As a result, heat is produced due to viscous force. The rate of production of heat when the sphere attains its terminal velocity, is proportional to

A

r³

B

r²

C

r⁵

D

r⁴

Question 30: Palette 30/85

NEET 2018 MCQ

The power radiated by a black body is P and it radiates maximum energy at wavelength, $\lambda $₀ . If the temperature of the black body is now changed so that it radiates maximum energy at wavelength ${3 \over 4}{\lambda _0}$, the power radiated by it becomes nP. The value of n is

A

${3 \over 4}$

B

${4 \over 3}$

C

${{256} \over {81}}$

D

${{81} \over {256}}$

Question 31: Palette 31/85

NEET 2018 MCQ

Two wires are made of the same material and have the same volume. The first wire has cross-sectional area A and the second wire has cross-sectional area 3A. If the length of the first wire is increased by $\Delta $l on applying a force F, how much force is needed to stretch the second wire by the same amount?

A

6F

B

F

C

9F

D

4F

Question 32: Palette 32/85

NEET 2017 MCQ

A U tube with both ends open to the atmosphere, is partially filled with water. Oil, which is immiscible with water, is poured into one side until it stands at a distance of 10 mm above the water level on the other side. Meanwhile the water rises by 65 mm from its original level (see diagram). The density of the oil is

A

425 kg m^$-$3

B

800 kg m^$-$3

C

928 kg m^$-$3

D

650 kg m^$-$3

Question 33: Palette 33/85

NEET 2017 MCQ

The bulk modulus of a spherical object is 'B'. If it is subjected to uniform pressure 'P', the fractional decrease in radius is

A

${B \over {3p}}$

B

${{3p} \over B}$

C

${p \over {3B}}$

D

${p \over B}$

Question 34: Palette 34/85

NEET 2017 MCQ

A spherical black body with a radius of 12 cm radiates 450 watt power at 500 K. If the radius were halved and the temperature doubled, the power radiated in watt would be

A

450

B

1000

C

1800

D

225

Question 35: Palette 35/85

NEET 2017 MCQ

Two rods A and B of different materials are welded together as shown in figure. Their thermal conductivities are K₁ and K₂. The thermal conductivity of the composite will be

A

${{3\left( {{K_1} + {K_2}} \right)} \over 2}$

B

${K_1} + {K_2}$

C

$2\left( {{K_1} + {K_2}} \right)$

D

${{{K_1} + {K_2}} \over 2}$

Question 36: Palette 36/85

NEET 2016 MCQ

A rectangular film of liquid is extended from (4 cm $ \times $ 2 cm) to (5 cm $ \times $ 4 cm). If the work done is 3 $ \times $ 10^$-$4 J, the value of the surface tension of the liquid is

A

0.250 N m^$-$1

B

0.125 N m^$-$1

C

0.2 N m^$-$1

D

8.0 N m^$-$1

Question 37: Palette 37/85

NEET 2016 MCQ

Two identical bodies are made of a material for which the heat capacity increases with temperature. One of these is at 100^oC, while the other one is at 0^oC. If the two bodies are brought into contact, then, assuming no heat loss, the final common temperature is

A

50 ^oC

B

more than 50 ^oC

C

less than 50 ^oC but greater than 0 ^oC

D

0 ^oC

Question 38: Palette 38/85

NEET 2016 MCQ

Three liquids of densities $\rho $₁, $\rho $₂  and $\rho $₃ (with $\rho $₁ > $\rho $₂ > $\rho $₃), having the same value of surface tension T, rise to the same height in three identical capillaries. The angles of contact $\theta $₁, $\theta $₂ and $\theta $₃ obey

A

${\pi \over 2} > {\theta _1} > {\theta _2} > {\theta _3} \ge 0$

B

0 $ \le $ $\theta $₁ < $\theta $₂ < $\theta $₃ < ${\pi \over 2}$

C

${\pi \over 2} < {\theta _1} < {\theta _2} < {\theta _3} < \pi $

D

$\pi > {\theta _1} > {\theta _2} > {\theta _3} > {\pi \over 2}$

Question 39: Palette 39/85

NEET 2016 MCQ

A body cools from a temperature 3T to 2T in 10 minutes. The room temperature is T. Assume that Newton's law of cooling is applicable. The temperature of the body at the end of next 10 minutes will be

A

${7 \over 4}\,$ T

B

${3 \over 2}$ T

C

${4 \over 3}$ T

D

T

Question 40: Palette 40/85

NEET 2016 MCQ

Two non-mixing liquids of densities $\rho $ and n$\rho $ (n > 1) are put in a container. The height of each liquid is h. A solid cylinder of length L and density d is put in this container. The cylinder floats with its axis vertical and length $\rho $L ($\rho $ < 1) in the denser liquid. The density d is equal to

A

$\left\{ {2 + \left( {n - 1} \right)p} \right\}\rho $

B

$\left\{ {1 + \left( {n - 1} \right)p} \right\}\rho $

C

$\left\{ {1 + \left( {n + 1} \right)p} \right\}\rho $

D

$\left\{ {2 + \left( {n + 1} \right)p} \right\}\rho $

Question 41: Palette 41/85

NEET 2016 MCQ

A black body is at a temperature of 5760 K. The energy of radiation emitted by the body at wavelength 250 nm is U₁, at wavelength 500 nm is U₂ and that at 1000 nm is U₃. Wien's constant, b = 2.88 $ \times $ 10⁶ nm K. Which of the following is correct ?

A

U₁ > U₂

B

U₂ > U₁

C

U₁ = 0

D

U₃ = 0

Question 42: Palette 42/85

NEET 2016 MCQ

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 [Latent heat of ice is $3.4 \times {10^5}$ J/kg and g = 10 N/Kg]

A

136 km

B

68 km

C

34 km

D

544 km

Question 43: Palette 43/85

NEET 2016 MCQ

Coefficient of linear expansion of brass and steel rods are $\alpha $₁ and $\alpha $₂. Lengths of brass and steel rods are $l$₁ and $l$₂ respectively. If ($l$₁ $-$ $l$₂) is maintained same at all temperatures, which one of the following relations holds good?

A

$\alpha $₁$l$₂ = $\alpha $₂ ²$l$₁

B

$\alpha $₁$l$₁ = $\alpha $₂l₂

C

$\alpha $₁$l$₂ = $\alpha $₂$l$₁

D

$\alpha $₁$l$₂² = $\alpha $₂$l$₁²

Question 44: Palette 44/85

NEET 2015 MCQ

Water rises to a height h in capillary tube. If the length of capillary tube above the surface of water is made less than h, then

A

water rises upto a point a little below the top and stays there.

B

water does not rise at all.

C

water rises upto the tip of capillary tube and then starts overflowing like a fountain.

D

water rises upto the top of capillary tube and stays there without overflowing.

Question 45: Palette 45/85

NEET 2015 MCQ

The cylindrical tube of a spray pump has radius R, one end of which has n fine holes, each of radius r. If the speed of the liquid in the tube is V, the speed of the ejection of the liquid through the holes is

A

${{VR{}^2} \over {{n^3}{r^2}}}$

B

${{{V^2}R} \over {nr}}$

C

${{V{R^2}} \over {{n^2}{r^2}}}$

D

${{V{R^2}} \over {n{r^2}}}$

Question 46: Palette 46/85

NEET 2015 MCQ

The value of coefficient of volume expansion of glycerin is 5 $ \times $ 10^$-$4 K^$-$1. The fractional change in the density of glycerin for a rise of 40^oC in its temperature, is

A

0.025

B

0.010

C

0.015

D

0.020

Question 47: Palette 47/85

NEET 2015 MCQ

The Young's modulus of steel is twice that of brass. Two wires of same length and of same area of cross section, one of steel and another of brass are suspended from the same roof. If we want the lower ends of the wires to be at the same level, then the weights added to the steel and brass wires must be in the ratio of

A

4 : 1

B

1 : 1

C

1 : 2

D

2 : 1

Question 48: Palette 48/85

NEET 2015 MCQ

On observing light from three different starts P, Q and R, it was found that intensity of violet colour is maximum in the spectrum of P, the intensity of green colour is maximum in the spectrum of R and the intensity of red colour is maximum in the spectrum of Q. If T_P, T_Q and T_R are the respective absolute temperatures of P, Q and R, then it can be conclued from the above observations that

A

T_P < T_R < T_Q

B

T_P < T_Q < T_R

C

T_P > T_Q > T_R

D

T_P > T_R > T_Q

Question 49: Palette 49/85

NEET 2015 MCQ

The two ends of a metal rod are maintained at temperatures 100^oC and 110^oC. The rate of heat flow in the rod is found to be 4.0 J/s. If the ends are maintained at temperatures 200^oC and 210^oC, the rate of heat flow will be

A

8.0 J/s

B

4.0 J/s

C

44.0 J/s

D

16.8 J/s

Question 50: Palette 50/85

NEET 2015 MCQ

The approximate depth of an ocean is 2700 m. The compressiblity of water is 45.4 $ \times $ 10^$-$11 Pa^$-$1 and density of water is 10³ kg/m³. What fractional compression of water will be obtained at the bottom of the ocean?

A

1.2 $ \times $ 10^$-$2

B

1.4 $ \times $ 10^$-$2

C

0.8 $ \times $ 10^$-$2

D

1.0 $ \times $ 10^$-$2

Question 51: Palette 51/85

NEET 2015 MCQ

A wind with speed 40 m/s blows parallel to the roof of a house. The area of the roof is 250 m². Assuming that the pressure inside the house is atmospheric pressure, the force exerted by the wind on the roof and the direction of the force will be $({\rho _{air}} = 1.2kg/{m^3})$

A

2.4 $ \times $ 10⁵ N, upwards

B

2.4 $ \times $ 10⁵ N, downwards

C

4.8 $ \times $ 10⁵ N, downwards

D

4.8 $ \times $ 10⁵ N, upwards

Question 52: Palette 52/85

NEET 2014 MCQ

Steam at 100^oC is passed into 20 g of water at 10^oC. When water acquires a temperature of 80^oC, the mass of water present will be
[Take specific heat of water = 1 cal g^{$-$1 o}C^$-$1 and latent heat of steam = 540 cal g^$-$1]

A

24 g

B

31.5 g

C

42.5 g

D

22.5 g

Question 53: Palette 53/85

NEET 2014 MCQ

A certain number of spherical drops of a liquid of radius r coalesce to form a single drop of radius R and volume V. If T is the surface tension of the liquid, then

A

energy = 4VT $\left( {{1 \over r} - {1 \over R}} \right)$ is released.

B

energy = 3VT$\left( {{1 \over r} + {1 \over R}} \right)$ is absorbed.

C

energy = 3VT$\left( {{1 \over r} - {1 \over R}} \right)$ is released

D

energy is neither released nor absorbed.

Question 54: Palette 54/85

NEET 2014 MCQ

Copper of fixed volume V is drawn into wire of length $l$. When this wire is subjected to a constant force F, the extension produced in the wire is $\Delta $$l$. Which of the following graphs is a straight line ?

A

$\Delta $$l$ versus 1/$l$

B

$\Delta $$l$ versus $l$²

C

$\Delta $$l$ versus 1/$l$²

D

$\Delta $$l$ versus $l$

Question 55: Palette 55/85

NEET 2014 MCQ

Certain quantity of water cools from 70^oC to 60^oC in the first 5 minutes and to 54^oC in the next 5 minutes. The temperature of the surroundings is

A

45^oC

B

20^oC

C

42^oC

D

10^oC

Question 56: Palette 56/85

NEET 2013 MCQ

The density of water at 20^oC is 998 kg/m³ and at 40^oC is 992 kg/m³. The coefficient of volume expansion of water is

A

3 $ \times $ 10^$-$4/^oC

B

2 $ \times $ 10^$-$4/^oC

C

6 $ \times $ 10^$-$4/^oC

D

10 $ \times $ 10^$-$4/^oC

Question 57: Palette 57/85

NEET 2013 MCQ

Two metal rods 1 and 2 of same lengths have same temperature difference between their ends. Their thermal conductivities are K₁ and K₂ and cross sectional areas A₁ and A₂, respectively. If the rate of heat conduction in 1 is four times that in 2, then

A

K₁A₁ = 4K₂A₂

B

K₁A₁ = 2K₂A₂

C

4K₁A₁ = K₂A₂

D

K₁A₁ = K₂A₂

Question 58: Palette 58/85

NEET 2013 MCQ

If the ratio of diameters, lengths and Young's modulus of steel and copper wires shown in the figure are p, q and s respectively, then the corresponding ratio of increase in their lengths would be

A

$\left( {{{5q} \over {7s{p^2}}}} \right)$

B

$\left( {{{7q} \over {5s{p^2}}}} \right)$

C

$\left( {{{2q} \over {5sp}}} \right)$

D

$\left( {{{7q} \over {5sp}}} \right)$

Question 59: Palette 59/85

NEET 2013 MCQ

A fluid is in streamline flow across a horizontal pipe of variable area of cross section. For this which of the following statements is correct?

A

The velocity is maximum at the narrowest part of the pipe and pressure is maximum at the widest part of the pipe.

B

Velocity and pressure both are maximum at the narrowest part of the pipe.

C

velocity and pressure both are maximum at the widest part of the pipe.

D

The velocity is minimum at the narrowest part of the pipe and the pressure is minimum at the widest part of the pipe.

Question 60: Palette 60/85

NEET 2013 MCQ

The molar specific heats of an ideal gas at constant pressure and volume are denoted by C_p and C_v, respectively. If  $\gamma $ = ${{{C_p}} \over {{C_v}}}$ and R is the universal gas constant, then C_v is equal to

A

${{\left( {\gamma - 1} \right)} \over R}$

B

$\gamma R$

C

${{1 + \gamma } \over {1 - \gamma }}$

D

${R \over {\left( {\gamma - 1} \right)}}$

Question 61: Palette 61/85

NEET 2013 MCQ

A piece of iron is heated in a flame. It first becomes dull red then becomes reddish yellow and finally turns to white hot. The correct explanation for the above observation is possible by using

A

Kirchhoff's Law

B

Newton's Law of cooling

C

Stefan's Law

D

Wien's displacement Law

Question 62: Palette 62/85

NEET 2013 MCQ

The following four wires are made of the same material. Which of these will have the largest extension when the same tension is applied?

A

length = 200 cm, diameter = 2 mm

B

length = 300 cm, diameter = 3 mm

C

length = 50 cm, diameter = 0.5 mm

D

length = 100 cm, diameter = 1 mm

Question 63: Palette 63/85

NEET 2013 MCQ

The wettability of a surface by a liquid depends primarily on

A

density

B

angle of contact between the surface and the liquid

C

viscosity

D

surface tension

Question 64: Palette 64/85

NEET 2012 MCQ

A slab of stone of area 0.36 m² and thickness 0.1 m is exposed on the lower surface to steam at 100^oC. A block of ice at 0^oC rests on the upper surface of the slab. In one hour 4.8 kg of ice is melted. The thermal conductivity of slab is
(Given latent heat of fusion of ice = 3.36 $ \times $ 10⁵ J kg^$-$1)

A

1.24 J/m/s/^oC

B

1.29 J/m/s/^oC

C

2.05 J/m/s/^oC

D

1.02 J/m/s/^oC

Question 65: Palette 65/85

NEET 2012 MCQ

If the radius of a star is R and it acts as a black body, what would be the temperature of the star, in which the rate of energy production is Q?

A

${Q \over {4\pi {R^2}\sigma }}$

B

${\left( {{Q \over {4\pi {R^2}\sigma }}} \right)^{ - 1/2}}$

C

${\left( {{{4\pi {R^2}Q} \over \sigma }} \right)^{1/4}}$

D

${\left( {{Q \over {4\pi {R^2}\sigma }}} \right)^{1/4}}$

Question 66: Palette 66/85

NEET 2012 MCQ

Liquid oxygen at 50 K is heated to 300 K at constant pressure of 1 atm. The rate of heating is constant. Which one of the following graphs represents the variation of temperature with time ?

A

B

C

D

Question 67: Palette 67/85

NEET 2010 MCQ

The total radiant energy per unit area, normal to the direction of incidence, received at a distance R from the centre of a star of radius r, whose outer surface radiates as a black body at a temperature TK is given by

A

${{\sigma {r^2}{T^4}} \over {{R^2}}}$

B

${{\sigma {r^2}{T^4}} \over {4\pi {R^2}}}$

C

${{\sigma {r^2}{T^4}} \over {{R^4}}}$

D

${{4\pi \sigma {r^2}{T^4}} \over {{R^2}}}$

Question 68: Palette 68/85

NEET 2010 MCQ

Assuming the sun to have a spherical outer surface of radius r, radiating like a black body at temperature t^oC, the power received by a unit surface, (normal to the incident rays) at a distance R from the centre of the sun is
where $\sigma $ is the Stefan's constant.

A

${{{r^2}\sigma {{\left( {t + 273} \right)}^4}} \over {4\pi {R^2}}}$

B

${{16{\pi ^2}{r^2}\sigma {t^4}} \over {{R^2}}}$

C

${{{r^2}\sigma {{\left( {t + 273} \right)}^4}} \over {{R^2}}}$

D

${{4\pi {r^2}\sigma {t^4}} \over {{R^2}}}$

Question 69: Palette 69/85

NEET 2010 MCQ

A cylindrical metallic rod in thermal contact with two reservoirs of heat at its two ends conducts an amount of heat Q in time t. The metallic rod is melted and the material is formed into a rod of half the radius of the original rod. What is the amount of heat conducted by the new rod, when placed in thermal contact with the two reservoirs in time t?

A

${Q \over 4}$

B

${Q \over {16}}$

C

2Q

D

${Q \over 2}$

Question 70: Palette 70/85

NEET 2009 MCQ

The two ends of a rod of length L and a uniform cross-sectional area A are Kept at two temperatures T₁ and T₂ (T₁ > T₂). The rate of heat transfer, ${{dQ} \over {dt}}$ through the rod in a steady state is given by :

A

${{dQ} \over {dt}} = {{k\left( {{T_1} - {T_2}} \right)} \over {LA}}$

B

${{dQ} \over {dt}} = kLA({T_1} - {T_2})$

C

${{dQ} \over {dt}} = {{kA\left( {{T_1} - {T_2}} \right)} \over L}$

D

${{dQ} \over {dt}} = {{kL\left( {{T_1} - {T_2}} \right)} \over A}$

Question 71: Palette 71/85

NEET 2009 MCQ

A black body at 227^oC radiates heat at the rate of 7 cals/cm²s. At a temperature of 727^oC, the rate of heat radiated in the same units will be

A

50

B

112

C

80

D

60

Question 72: Palette 72/85

NEET 2008 MCQ

On a new scale of temperature (which is linear) and called the W scale, the freezing and boiling points of water are 39^oW and 239^oW respectively. What will be the temperature on the new scale, corresponding to a temperature of 39^oC on the Celsius scale ?

A

200^oW

B

139^oW

C

78^oW

D

117^oW

Question 73: Palette 73/85

NEET 2007 MCQ

A black body is at 727^oC. It emits energy at a rate which is proportional to

A

(1000)⁴

B

(1000)²

C

(727)⁴

D

(727)²

Question 74: Palette 74/85

NEET 2007 MCQ

Assuming the sun to have a spherical outer surface of radius r, radiating like a black body at temperature t^oC, the power received by a unit surface, (normal to the incident rays) at a distance R from the centre of the sun is
where $\sigma $ is the Stefan's constant.

A

${{{r^2}\sigma {{\left( {t + 273} \right)}^4}} \over {4\pi {R^2}}}$

B

${{16{\pi ^2}{r^2}\sigma {t^4}} \over {{R^2}}}$

C

${{{r^2}\sigma {{\left( {t + 273} \right)}^4}} \over {{R^2}}}$

D

${{4\pi {r^2}\sigma {t^4}} \over {{R^2}}}$

Question 75: Palette 75/85

NEET 2006 MCQ

A black body at 1227^oC emits radiations with maximum intensity at a wavelength of 5000 $\mathop A\limits^ \circ $. If the temperature of the body is increased by 1000^oC, the maximum intensity will be observed at

A

3000 $\mathop A\limits^ \circ $

B

4000$\mathop A\limits^ \circ $

C

5000$\mathop A\limits^ \circ $

D

6000$\mathop A\limits^ \circ $

Question 76: Palette 76/85

NEET 2005 MCQ

Which of the following rods, (given radius r and length $l$) each made of the same material and whose ends are maintained at the same temperature will conduct most heat ?

A

r = r₀, $l$ = $l$₀

B

r = 2r₀, $l$ = $l$₀

C

r = r₀, $l$ = 2$l$₀

D

r = 2r₀, $l$ = 2$l$₀

Question 77: Palette 77/85

NEET 2004 MCQ

If $\lambda $_m denotes the wavelength at which the radioactive amission from a black body at a temperature TK is maximum, then

A

${\lambda _m}\, \propto \,{T^4}$

B

${\lambda _m}$ is independent of T

C

${\lambda _m}$ $ \propto $ T

D

${\lambda _m}\, \propto \,{T^{ - 1}}$

Question 78: Palette 78/85

NEET 2003 MCQ

Consider a compound slab consisting of two different materials having equal thicknesses and thermal conductivities K and 2K, respectively. The equivalent thermal conductivity of the slab is

A

${2 \over 3}K$

B

$\sqrt 2 K$

C

3 K

D

${4 \over 3}K$

Question 79: Palette 79/85

NEET 2002 MCQ

For a black body at temperature 727^oC, its radiating power is 60 watt and temperature of surrounding is 227^oC. If temperature of black body is changed to 1227^oC then its radiating power will be

A

304 W

B

320 W

C

240 W

D

120 W

Question 80: Palette 80/85

NEET 2002 MCQ

Which of the following is best close to an ideal black body?

A

black lamp

B

cavity maintained at constant temperature

C

platinium black

D

a lump of charcoal heated to high temperature.

Question 81: Palette 81/85

NEET 2002 MCQ

Consider two rods of same length and different specific heats (S₁, S₂), conductivities (K₁, K₂) and area of cross-sections (A₁, A₂) and both having temperatures T₁ and T₂ at their ends. If rate of loss of heat due to conduction is equal, then

A

K₁A₁ = K₂A₂

B

${{{K_1}{A_1}} \over {{S_1}}} = {{{K_2}{A_2}} \over {{S_2}}}$

C

K₂A₁ = K₁A₂

D

${{{K_2}{A_1}} \over {{S_2}}} = {{{K_1}{A_2}} \over {{S_1}}}$

Question 82: Palette 82/85

NEET 2002 MCQ

The Wien's displacement law express relation between

A

wavelength corresponding to maximum energy and temperature

B

radiation energy and wavelength

C

temperature and wavelength

D

colour of light and temperature.

Question 83: Palette 83/85

NEET 2002 MCQ

Unit of Stefan's constant is

A

watt m² K⁴

B

watt m²/K⁴

C

watt/m² K

D

watt/m²K⁴

Question 84: Palette 84/85

NEET 2001 MCQ

A cylindrical rod having temperature T₁ and T₂ at its end. The rate of flow of heat Q₁ cal/sec. If all the linear dimension are doubled keeping temperature constant, then rate of flow of heat Q₂ will be

A

4Q₁

B

2Q₁

C

${{{Q_1}} \over 4}$

D

${{{Q_1}} \over 2}$

Question 85: Palette 85/85

NEET 2000 MCQ

A black body has maximum wavelength $\lambda $_m at 2000 K. Its corresponding wavelength at 3000 K will be

A

${3 \over 2}{\lambda _m}$

B

${2 \over 3}{\lambda _m}$

C

${{16} \over {81}}{\lambda _m}$

D

${{81} \over {16}}{\lambda _m}$