Properties of matter Questions and Answers

A uniform rod of mass M length L area of cross section A and Young s modulus Y is suspended vertically from a fixed support Then YH AHGU G Hi GwHA M Atis L KA CHIT A guzga quic Y EEEz y acce A G A CAR Total elongation of rod is MgL 2AY Correct Answer Your Answer B the rod is D MgL 2AY 2 Total elastic potential energy stored in M g L 4AY G3 uka ha uzuzu Kufu kuf C The elastic potential energy stored in the 7 M g L upper half of rod is 48 AY G3 34 gka GzzY KAA Guf 7 M g L 48 AY M g L 4AY upper half of rod is 2 Correct Answer Your Answer The elastic potential energy stored in the M g L 48 4 fa zzu Kft

1 Two chairs A and B are in an empty room overnight Chair A is made of steel while chair B is made of wood In the night and in the morning the temperature of the room is 290 K In the morning a person chooses between Chair A and Chair B as the seat by feeling touching the chair and choosing one which feels warmer Person chooses BLANK 1 as it feels warmer because BLANK 3 BLANK 4 than BLANK 5 A BLANK 1 Chair A Chair B neither chair B BLANK 2 metal wood air human body C BLANK 3 higher lower different same BLANK 2 has D BLANK 4 heat capacity heat conductivity electrical resistance E BLANK 5 metal wood air human body

Two prisms have refracting angles 1 and 1 5 respectively They are made of materials of refractive index and respectively If deviation in a light ray by the combination of these two prisms to be zero then choose the correct option 1 3 2 1 2 2 3 3 2 3 0 4 3 2 1

o A potentiometer consists of a wire of length 4 m and resistance 10 Q2 It is connected to a cell of e m f 2 V The potential difference per unit length S of the wire will be 1 5 V m 3 0 5 V m 2 2 V m 4 10 V m 84

Two friends Ashok and Arup wanted to prepare saturated solutions of a water soluble solute One day they took a thermometer and observed the room temperature as 30 C From the solubility chart they came to know that the solubility of that solute in water at 30 C is 20 g Using electronic balance they accurately measured 50 g of water in two different beakers Then Ashok and Arup measured 11 g and 9 g solute respectively and added to 50 g of water and started stirring continuously On the basis of their preparation of solutions answer the following questions After dissolving 9 g of the solute what is the exact amount of solute should be dissolved by Arup to get the saturated solution at 30 C a 5 g b lg c 3g d 4 g

1 A wooden wheel of radius R is made of two semi circular parts see figure The two parts are held together by a ring made of a metal strip of cross sectional area S and length L L is slightly less than 2 TR To fit the ring on the wheel it is heated so that its temperature rises by AT and it just steps over the wheel As it cools down to surrounding temperature it presses the semicircular parts together If the coefficient of linear expansion of the metal is a and its Young s modulus is Y the force that one part of the wheel applies on the other part is a 2 SY AT c SY AT b SY AT d 2SY AT R

conductivity of the first rod then rate of melting of ic will be A 0 25 gm sec B 0 5 gm sec Duration 3 00 00 Time Left 1 2 C 1 gm sec D 2 gm sec

Q 1 If x grams of steam at 100 C becomes water at 100 C which converts y grams of ice at 0 C into water at 100 C then the ratio x y will be Lice 80 cal g Lsteam 540 cal g Swater 1 cal g C 1 3 3 3 1 2 4 27 4 4

2 2 The dispersion relation for a low density plasma is o a c k where wo is the plasma frequency and c is the speed of light in free space The relationship between the group velocity vg and phase velocity vp S a vp g P b Vp 2 g c VpVg d Vg v 2 P

The coefficient of volume expansion 49x10 5 K Calculate the fractional change in its density when the temperature is raised by 30 C AMU Engg 2010 a 7 5 10 b 3 0 10 c 1 5x10 d 1 1 10 radi

0 1 Two mechanical waves y 2 sin 2x 50 t 2x y 4 sin 2x ax 100 t propagate in a medium with same speed Sin 501 2n los 11 50t 2m A The ratio of their intensities is 1 16 B The ratio of their intensities is 1 4 C The value of a is 4 units I 2x4 1 4XQ 2 16 Q x 42 27 D The value of a is 2 units 00sed l bus ant to poian lex J2 4 x 4 4 16

me 9 ad the d B A ball falling in a lake of depth 200 m shows 0 1 decrease in its volume at the bottom What is the bulk modulus of the material of the ball 1 19 6 x 10 N m 2 19 6 x 100 N m 3 19 6 x 100 N m 4 19 6 x 10 N m OPERS OF MATTER AND RUD ME

The dimensions of two wires A and B are the same 9 But their materials are different Their load extension graphs are shown If Y and Y are the values of Young s modulus of elasticity of A and B respectively then 1 Y Y 2 Y Y 3 Y Y 4 Y 2Y load extension 10

A slender prismatic rod of circular cross sectional area 100 mm is subjected to a force of 100 kN If Young s modulus of the rod material be 100 GPa its diametral contraction will be consider Poison s ratio 0 25 A 25 10 3 B 25 x 10 4 C 25 x 10 2 D None of the above 20

and heated Then A between two rigid walls A compressive thermal strain will be developed in the rod A tensile thermal strain will be developed in the rod The value of thermal stress will be equal to y Ase where all the symboles have their appropriate meaning None of the above statements are correct

4 M M m In a U tube the liquid levels are equal in the state of equilibrium If the U tube is taken to the with an accelerated motion the liquid level 1 will be higher in arm A than in arm B 2 will bel lower in arm A than in arm B 3 will remain equal in both the arm 4 A gap will be created between the liquid in two arma A

A blacksmith fixes iron ring on rim of woods wheel of a cart The diameter of rim and iron ring are 3 243 m and 3 231 m respectively at 27 C To what temperature should ring be heated to fit on rim a 1 2 x 10 5 K 1 NCERT Pg 283 1 309 5 C 2 336 5 C 3 412 C

ber 10 A plane is in level flight and each of its wings has an area 20 m If the speed of air on upper and lower surfaces are 80 m s and 70 m s respectively then the mass of plane is density of air 1 kg m NCERT Pg 271 1 1500 kg 2 1700 kg 3 1650 kg 4 1750 kg

13 The edge of an aluminum cube is 10 cm One face of the cube is firmly fixed to a vertical wall A mass of 100 kg is attached to the opposite face of the cube The vertical deflection of this face is G 25 109 Pa 1 4 x 10 7 m 3 2 10 6 m NCERT XI Pg 248 2 3 x 10 6 m 4 1 x 10 6 m

4 1 x 10 6 m 14 A rigid bar of mass 15 kg is supported symmetrically by three wires each 2 0 m long Those at each end are of copper and the middle one is of iron If tension in each rod is same the ratio of diameters is nearly 1 6 3 4 2 The density of NCERT XI Pg 248 2 0 8 4 2 0

A triangular lamina of area A and height h is immersed in a liquid of density in a vertical plane with its base on the surface of the liquid The thrust on the lamina is a Ap c Apgh Apgh b 3 d Ap Apgh Apgh

3 A hollow sphere of radius R with a small hole at the bottom is completely filled with a liquid of uniform density see figure The liquid drains out of the sphere through the hole at an uniform rate in time T Which one of the following graphs A B C D qualitatively represents the height h of the center of mass of sphere liquid inside it measured from the bottom of the sphere with time R O hole I R R T 2 1 2 B h R R T 2 7 2 T

5 Two soap bubbles of equal radii 4cm are touching each other with an intermediate film separating them Surface tension of solution forming bubbles is 7 10 N m The distance between the centres of soap bubbles is in cm A 4 B 6 C 8 D 5

height They are connected by a tube see figure alf the liquid in container A is heated in which direction will the liquid flow through the tube b If the liquid in the container B is heated in which direction will the liquid flow through the tube Assume that the containers do not expand on heating A B

A uniform rod of length cross sectional area A and Young s modulus Y is subjected cross sect onal area A and Young s modulus Y is subjected to to two forces F and 2F at its two ends stretching the rod The heat generated in the rod is found to be 10a b F 1 12AY Find a b a b Positive integers

P A point source of power P is placed on the axis of a thin hemispherical shell as shown The shell has a radius of 3m and behaves like a perfect black body If the steady state temperature of shell is T Find T after rounding off Take P 2400 W G stefan s const 4m

17 A particle of mass 1 96 10 15 kg is kept is equilibrium between two horizontal metal plates having potential difference of 400 V separated apart by 0 02 m then the charge on the particle is e electronic charge A 3e B 6e C 2e D 5e

A dip circle shows an apparent dip of 45 at a place where the true dip is 30 If the dip circle is rotated through 90 what apparent dip will it show 1 cot 2 3 tan 2 An olgotron cot 2 4 45 og along the lino AP which ligg

A wire extends by l mm when a weight W is hanged from it If the wire passes through the pulley and a weight W is attached at one end whereas 3W is attached at the other end then the extension in mm of the wire is Question Type Single Correct Type 1 2 3 e 2l 21 3

When two soap bubbles of different radii coalesce some portions of their surface make a common surface At any point on the circumference of the common surface the three surface meet at angles a and y What relation should these angles bear A a B B B Y C y D B Y a Y B

3 3 m 4 1 89 m While visiting the orthopedics department AIIMS Delhi Ram notices a datasheet whic mentions that the human femoral cortical bor has an average Young s modulus equal 19000 MPa A stress of approximately 200 MP is the tensile strength of the bone The maximu bearable strain of the bone will be 1 3 5 2 2 9 3 1 05 4 0 15

3 4 23 The bulk modulus of water is 3 x 10 N m The extra pressure required to increase the density of water by 0 2 is 1 1 5x 10 N m 3 10 N m 2 3 x 10 N m 4 6x 10 N m

Online Mock Test Series for NEET 2020 43 The Young s modulus of the material of the wire length L and radius r is Y N m If the length reduced to and radius2 the Young modulus will be 1 IN 3 2Y 2 Y 4 4Y

A solid sphere of radius 3cm made of material of bulk modulus 2x10 N m is surrounded by a liquid in a cylindrical container A massless piston of area 8x10 m area of the container is also same floats on the surface of liquid A mass of 5kg is placed on the piston to compress the liquid change in radius of 0 sphere in A is

Two identical ropes A and B of uniform mass per unit length arc suspended from the ceiling and are made to pass through an almost inertia less metallic tubular structure C as shown in the figure The structure is made by welding two identical bent tubes There is no friction between the ropes and the tubes Initially the structure is held at rest and then released What will happen a It will not move at all b It will move downwards with speed decreasing at the rate 0 5g c It will move downwards with speed increasing at the rate 0 5g d The rope will heat up A C B

Test 3 Code A 43 Two wires w and w are made of the same material and have the same volume However wire w has cross sectional area A and wire w has cross sectional area 3 A If the length of wire w increases by Ay on applying force F how much force is needed to stretch the wire w by the same amount 1 F 2 4F

92 A uniform steel rope 400 meters long is hang vertically The weight of the steel is 7 8 gm cm and D 21000 kg mm2 The ratio of elongation of first 150 meters to that is first 300 meters would be a 16 1 c 2 1 b 4 1 d 1 4

12 A wire is suspended by one end At the othe a weight of 20N is hung If the increase in leng wire is 1mm the increase in the elastic pot energy of the wire will be 0 0 0 01 J 3 0 04 J 0 02 J 4 1 00 J DATO

To what depth below the surface of sea should a rubber ball be taken so as to decreases its volume by 0 1 Average density of sea water 1000kg m bulk modulus of rubber 9 108 1 9m 21 400m N and g 10ms 21 m 2 18m in 00

Rod of constant cross section moves towards right with constant acceleration Graph of stress and distance from left end is given as in figure If density of material of rod at cross section 1 is 9 gm cm Find density at cross section 2 0 O 16 gm cm 20gm cm 24 gm cm 12gm cm Stress

Water density p is flowing through the uniform tube of cross sectional area A with a constant speed as shown The magnitude of force exerted by the water on the curved portion of the tube is 1 3pAv 3 2pAv A rod of 60 A Medica 2 pAv kent in PAV 2 shown in

ns 12 0 A wire of length L area of cross section A is hanging from a fixed support The length of the wire changes to L when mass M is suspended from its free end The expression for Young s modulus is 1 3 MgL A L L Mg L L AL 4 MgL AL MgL AL

28 A load causes a wire to stretch by the amount s If the same load is applied to another wire of the same material but four times as long and twice the diameter The second wire will stretch by the amount O A 4s O B 2s O C O D S

The potential energy stored in a certain kind of an elastic rope is a function of its length L in meters and can be evaluated using the equation P 10 k L 3 where k is some positive constant What is the potential energy of the rope in terms of k when it is streched to a length 2 meters greater than the length when it has minimum potential energy a b c d 10 k 10 k 10 4k 10 5k

One end of a steel wire of area of cross section 3 mm is attached to the ceiling of an elevator moving up with acceleration of 2 2 m s If a load of 8 kg attached at its free end then stress developed in the wire will be g 9 8 m s 8 x 106 N m 16 x 106 N m 20 x 106 N m 32 x 106 N m

The end of a capillary tube with a radius r is immersed vertically into water an the water rises up inside the tube T is the surface tension and pis the density water If the angle of contact is zero A The water rises to a height h 2T pgr B The forces of surface tension perform the work 4 T p g C The potential energy of water increases by 2 T pg D The heat evolved during the process is 2 T p g space for rough work Page

A cylindrical tube with radius R wall thickness A is filled with and ideal gas with pressure P What is maximum pressure of gas it can with if the system is taken to vacuum rom stand if the breaking stress of tube is

A capillary tube of radius R is immersed in water and water rises in it to a height H Mass of water in the capillary tube is M If the radius of the tube is doubled mass of water that will rise in the capillary tube will now be M 2M X M 2 ADA

A metallic rod breaks when strain produced is 0 2 The Young s modulus of material of rod is 2 x 1011 N m What should be the minimum area of cross section to support a load of 105 N 1 2 5 x 104 m 2 6 25 x 10 3 m 3 1 25 x 10 4 m 4 4 1 x 10 4 m

A parallel beam of radiation is incident first on a highly conducting sphere and then on a highly conducting cube as shown If both sphere and cube are made from same material same emissivity then which of the following is CORRECT O Question Type Single Correct Type 1 2 3 4 Steady state temperatures of sphere and cube are same Steady state temperature of sphere will depend on its size Steady state temperature of cube depends on its dimensions Steady state temperature of sphere is more than steady state temperature