IIT-JEE Physics Sample Paper - 1

 

PHYSICS

 

101.      In a compound microscope cross wires are fixed at the point

            1) Where the image is formed by the objective

            2) Where the image is formed by the eye-piece

            3) Where the focal point of the objective lies

            4) Where the focal point of the eyepiece lies

102.      Consider the following two statements A and B and identify the correct choice in the given answers

            A : Line spectra is due to atoms in gaseous state

            B : Band spectra is due to molecules

            1) Both A and B are false                                    2) A is true and B is false

            3) A is false and B is true                                    4) Both A and B are true

103.      Under minimum deviation condition in a prism, if a ray is incident at an angle 300, the angle  between the emergent ray and second refracting surface of the prism is

            1) 00                             2) 300                           3) 450                           4) 600

104.      A short bar magnet with its north pole facing north forms a neutral point at p in the horizontal plane. If the magnet is rotated by 900 in the horizontal plane, the net magnetic induction at P is ( Horizontal component of earth's magnetic field = BH )

            1) 0                               2) 2 BH                          3) Ö5/2 BH                     4) Ö5 BH

105.      Two similar bar magnets P and Q each of magnetic moment M are taken. If P is cut along its axial line and Q is cut along its equatorial line, all the four pieces obtained have each of

            1) equal pole strength                                         2) magnetic moment M/4

            3) magnetic moment M/2                                    4) magnetic moment M

106.      There is no couple acting when two bar magnets are placed coaxially separated by a distance because

            1) There are no forces on the ples

            2) The forces parallel and their lines of action do not coincide

            3) The forces are perpendicular each other

            4) The forces act along the same line

107.      The pole strength of a 12 cm long bar magnet is 20 A.m. The magnetic induction at a point 10 cm away from the centre of the magnet on its axial line is [ m0 / 4p = 10-7 Hm-1 ]

            1) 1.1 x 102 T                 2) 2.2 x 102 T                3) 1.1 x 10-2 T               4) 2.2 x 10-2 T

108.      Electric charges of 1mC, -mC amd mC are placed in air at the corners A, B and C respectively of an equilateral triangle ABC having length of eath of each side 10 cm. The resultant force on the charge at c is

            1) 0.9 N                         2) 1.8 N                         3) 2.2 N                         4) 3.6 N

 

 

 

109.      A charged particle of mass 5 x 10 kg is held stationary in space by placing it in an electric field of strength 106 NC-1 directed vertically downwards. The charge on the particle is

            (g = 10 ms2)

            1) -20 x 10-5 mC             2) -5 x 10-5 mC              3) 5 x 10-5 mC                4) 20 x 10-5 mC

110.      Two long parallel copper wires carrying currents in the opposite direction of 5A each. If the wires are separated by a distance of 0.5 m, then the force between the two wires is

            1) 10-5 N attractive force                                     2) 10 N-6 repulsive force

            3) 2 x 105 N attractive force                                 4) 2 x 10-6 N repulsive force

111.      An ammeter and voltmeter of resistance R are connected in series to an electric cell of negligible internal resistance. Their readings are A and V respectively. If another resistance R is connected in parallel with the voltmeter

            1) Both A and V will increase                              2) Both A and V will decrease

            3) A will decrease and V will increase                  4) A will increase and V will decrease

112.      Two electric charges 12 mC and -6 mC are placed 20 cm apart in air. There will be a point P at which electric potential is zero on the line joining these two charges and out side, excluding the region between them. The distance of P from -6mC charge is

            1) 0.10 cm                     2) 0.15 cm                     3) 0.20 m                      4) 0.25 m

113.      Two wires of equal diameters of resistivities P1 and P2 and lengths x1 and x2 respectively are joined in series. The equivalent resistivity of the combination is

            1) P1 x1 + P2 x2                 2) P1 x2 + P2 x1                3) P1 x2 + P2 x1                4) P1 x1 - P2 x2

                         x1 + x2                               x1 - x2                                 x1 + x2                             x1 - x2

114.      The X - ray wavelength of La line of platinum ( z = 78 ) is 1.30 A0. The x - ray wavelength La line of Molybdenum ( Z = 42 ) is

            1) 5.41 A0                      2) 4.20 A0                     3) 2.70 A0                     4) 1.35 A0

115.      When a metal surface is illuminated by a light of wavelengths 400 nm and 250 nm, the maximum velocities of the photo electrons ejected are V and 2V respectively. The work function of the metal is : ( h = Plank's constant, c = velocity of light in air )

            1) 2 hc x 106 J               2) 1.5 hc x 106 J            3) hc x 106 J                  4) 0.5 hc x106 J

116.      The energy of an x - ray photon wavelength 1.65 A0 is

            (h = 6.6 x 10-34 J - S, C = 3 x 108 ms-1 , 1 eV = 1.6 x 10-19 J)

            1) 3.5 K eV                    2) 5.5 KeV                     3) 7.6 K eV                    4) 9.5 K eV

117.      The ratio of the longest to shortest wavelengths in Bracket series of hydrogen spectra is

            1) 25/9                          2) 17/6                          3) 9/5                            4) 4/3

118.      In Bohr model of hydrogen atom, the ratio of periods of revolution of an electron in n = 2 and n = 1 orbits is

            1) 2:1                            2) 4:1                            3) 8:1                            4) 16:1

 

 

 

 

119.      To generate a power of 3.2 mega watts, the number of fissions of U235 per minute is

            ( Energy released per fission = 200 MeV, 1 eV = 1.6 x 10-9 J)

            1) 6 x 1018                           2) 6 x 1017                           3) 1017                                  4) 6 x 1016

120.      Consider the following statements A and B and identify the correct choice of the given     answers

            A : The width of the depletion layer in a p - n junction diode increases in forward bias

            B : In an intrinsic semiconductor the Fermi energy level is exactly in the middle of the forbidden gas

            1) A is true and B is false                                    2) Both A and B are false

            3) A is false and B is true                                    4) Both A and B are true

121.      The fundamental physical quantities that have same dimensions in the dimensional formulae of torque and angular momentum are

            1) mass, time                2) time, length               3) mass, length              4) time, mole

122.      If pressure P, velocity V and time T are taken as fundamental physical quantities, the dimensional formula of the force is

            1) PV2 T2                      2) P-1 V2 T2                   3) PVT2                         4) T-1 VT2

123.      The displacement r of a charge Q in an electric field E = e1 i + e2 j + e3 k is r = ai + bj. The work done is

            1) Q (ae1 + be2)                                                 2) Q Ö(ae12) + (be2)2

            3) Q (e1 + e2) Öa2 + b2                                       4) Q [ Öe12 +  e22 ] (a + b)

124.      A body is thrown vertically upwards with an initial velocity 4 reaches maximum height in 6 seconds. The ratio of distances travelled by the body in the first second and seventh second is

            1) 1:1                            2) 11:1                          3) 1:2                            4) 1:11

125.      A body is thrown horizontally from the top of a tower of 5 m height. It touches the ground at a distance of 10 m from the foot of the tower. The initial velocity of the body is (g = 10 ms-2)

            1) 2.5 ms-1                    2) 5 ms-1                       3) 10 ms-1                     4) 20 ms-1

126.      Four bodies P,Q,R,S are projected with equal velocities having angles of projection 150, 300, 450 and 600 with the horizontal respectively. The body having shortest range is

            1) P                              2) Q                              3) R                              4) S

127.      A force of 5 N waking an angle q with the horizontal acting on an object displaces it by 0.4 m along the horizontal direction. If the object gains kinetic energy of 1J, the horizontal component of the force is

            1) 1.5 N                         2) 2.5 N                         3) 3.5 N                         4) 4.5 N

128.      A body of mass m1 moving with a velocity 10 ms-1 collides with another body at rest of mass m2. After collision the velocities of the two bodies are 2 ms‑1 and 5 ms-1 respectively along the direction of motion of m1. The ratio m1 / m2 is

            1) 5/12                          2) 5/8                            3) 8/5                            4) 12/5

129.      A ball is projected vertically down with an initial velocity from a height of 20 m on to a horizontal floor. During the impact it looses 50% of its energy and rebounds to the same height. The initial velocity of its projection is ( g = 10 ms-2 )

            1) 20 ms-1                     2) 15 ms-1                            3) 10 ms-1                            4) 5 ms-1

130.      A 10 H.P. motor pumps out water from a well of depth 20 m and fills a water tank of volume 2238 liters at a height of 10 m from the ground. The running time of the motor to fill the empty water tank is ( g = 10 ms-2 )

            1) 5 minutes                  2) 10 minutes                3) 15 minutes                4) 20 minutes

131.      A body is sliding down an inclined plane having co-efficient of friction 0.5. If the normal reaction is twice that of the resultant downward force along the incline, the angle between the inclined plane and the horizontal is

            1) 150                            2) 300                           3) 450                           4) 600

132.      The moment of inertia of a sphere of mass M and radius R about an axis passing through its centre is 2/5 MR2. The radius of gyration of the sphere about a parallel axis to the above and tangent to the sphere is

            1) 7/5 R                         2) 3/5 R                         3) [Ö7/5]R                      4) [Ö3/5]R

133.      A wheel has a speed of 1200 revolutions per minute and is made to slow down at a rate of 4 radians The number of revolution it makes before coming to rest is

            1) 143                           2) 272                           3) 314                           4) 722

134.      R and r are the radii of the earth and moon respectively pe and pm are the densities of earth and moon respectively. The ratio of the accelerations due to gravity on the surfaces of earth to moon is

            1) R/r  pe / pm                      2) r/R  pe / pm                     3) r/R  pm / pr                      4) R/r  pm / pe

135.      The height of the point vertically above the Earth's surface at which acceleration due to gravity becomes 1% of its value at the surface is

            1) 8 R                            2) 9 R                           3) 10 R                          4) 20 R

136.      A body of mass 1 kg executing simple harmonic motion, its displacement y cm at t seconds is given by  Y = 6 sin (100 t + p/4). Its maximum kinetic energy is

            1) 6J                             2) 18J                           3) 24J                           4) 36 J

137.      A particle executing simple harmonic motion has an amplitude of 6 cm. Its acceleration at a distance from the mean position 2 cm is 8 cm / s2. The maximum speed of the particle is

            1) 8 cm / s                     2) 12 cm / s                   3) 16 cm / s                   4) 24 cm / s

 

 

 

138.      When a uniform wire of radius r is stretched by a 2 kg weight, the increase in its length is 2.00 mm. If the radius of the wire is r/2 and other conditions remaining the same, the increase in its length is

            1) 2.00 m                       2) 4.00 m                      3) 6.00 m                      4) 8.00 m

139.      8000 identical water drops are combined to form a big drop. Then the ratio of final surface energy to the initial surface energy of all the drops together is

            1) 1:10                          2) 1:15                          3) 1:20                          4) 1:25

140.      When a liquid in a glass vessel is heated, its apparent expansion is 10.30 x 10-4  /0C Same liquid when heated in a metal, its apparent expansion is 10.06 x 10-4 /0 C. The cooefficient of linear expansion of the metal is (coefficient of linear expansion of glass = 9 x 10-6 / 0 C)

            1) 51 x 10-6 /0C              2) 43 x 10-6 /0C             3) 25 x 10-6 /0C             4) 17 x 10-6 /0C

141.      A vessel is filled with an ideal gas at a pressure of 10 atmospheres and temperature 270 C Half of the mass of the gas is removed from the vessel and temperature of the remaining gas is increased to 870 C. Then the pressure of the gas in the vessel will be

            1) 5 atm                        2) 6 atm                        3) 7 atm                        4) 8 atm

142.      During an adiabatic process, if the pressure of an ideal gas is proportional to the cube of its temperature, the ration n = CP / Cv is (specific heat at constant volume = CV , Specific heat at constant pressure = CP )

            1) 3/5                            2) 4/3                            3) 5/3                            4) 3/2

143.      A flask is filled with 13 g of an ideal gas at 270 C and its temperature is raised to 520 C. The mass of the gas that has to be released to maintain the temperature of the gas in the flask at 520 C and the pressure remaining the same is

            1) 2.5 g                         2) 2.0 g                         3) 1.5 g                         4) 1.0 g

144.      An ideal gas at a pressure of 1 atmosphere and temperature of 270 C is compressed adiabatically its pressure becomes 8 times the initial pressure, then the final temperture is

            1) 6270 C                       2) 5270C                       3) 4270C                       4) 3270 C

145.      Two liquids at temperatures 600 C and 200 C respectively have masses in the ratio 3:4 and their specific heats in the ratio 4:5. If the two liquids are mixed, the resultant temperature is

            1) 700 C                        2) 500 C                        3) 400 C                        4) 350 C

146.      Two metal rods A and B of equal lengths and equal cross sectional areas are joined end to end. The coefficients of thermal conductivities of A and B are in the ratio 2:3. When the free end of A is maintained at 1000 C and the free end of B is maintained at 00 C, the temperature of the junction is

            1) 300 C                        2) 400 C                        3) 500 C                        4) 600 C

147.      The frequency of a stretched uniform wire under tension is in resonance with the fundamental frequency of a closed tube. If the tension in the wire is increased by 8N, it is in resonance with the first overtone of the closed tube. The initial tension in the wire is

            1) 1N                             2) 4N                            3) 8N                            4) 16N

 

148.      If a vibrating tuning fork of frequency 255 Hz is moving with a velocity 4 ms-1 perpendicular to a wall, the number of beats produced per second is (speed of sound in air = 340 ms-1)

            1) 3                               2) 4                               3) 5                               4) 6

149.      A source producing sound of frequency 170 Hz is approaching a stationary observer with a velocity 17 m/s. The apparent change in the wavelength of sound heard by the observe is

            (speed of sound in air = 340 ms-1)

            1) 0.1 m                        2) 0.2 m                        3) 0.4 m                        4) 0.5 m

150.      The focal length of the lenses of an astronomical telescope are 50 cm and 5 cm. The length of telescope when the image is formed at the least distance of distinct vision is

            1) 45 cm                        2) 55 cm                       3) 275/6 cm                   4) 325/6 cm

 

physics

 

            101) 1                    102) 4                    103) 4                    104) 4                    105) 3

            106) 4                    107) 1                    108) 2                    109) 2                    110) 2

            111) 4                    112) 3                    113) 1                    114) 1                    115) 1

            116) 3                    117) 1                    118) 3                    119) 1                    120) 3

            121) 3                    122) 1                    123) 1                    124) 2                    125) 3

            126) 1                    127) 2                    128) 2                    129) 1                    130) 3

            131) 3                    132) 3                    133) 3                    134) 1                    135) 2

            136) 2                    137) 2                    138) 4                    139) 3                    140) 4

            141) 2                    142) 4                    143) 4                    144) 4                    145) 4

            146) 2                    147) 1                    148) 4                    149) 1                    150) 4