SSC SCIENTIFIC ASSISTANT IMD EXAM :HELD ON 25-NOV-2017 (Shift-1) (PHYSICS)
SSC SCIENTIFIC ASSISTANT IMD EXAM :HELD ON 25-NOV-2017 (Shift-1)
(PHYSICS)
QID : 101 - Becquerel is a unit of?
1) Radioactivity
2) Length
3) Frequency
4) Area
Correct Answer: Radioactivity
QID : 102 - If 'x' is displacement, time taken 't', initial velocity 'u', final velocity v and acceleration 'a'. Which of the following equations is true?
1) a = 2x/t2 + 2u/t
2) a = 2x/t - 2u/t2
3) a = 2x/t + 2u/t2
4) a = 2x/t2 - 2u/t
Correct Answer: a = 2x/t2 - 2u/t
QID : 103 - The law of _____________ was inferred by Galileo from observations of motion of a ball on a double inclined plane.
1) momentum
2) inertia
3) energy
4) equilibrium
Correct Answer: inertia
QID : 104 - If 'a' projectile is thrown with velocity 'v' and making an angle 'θ' with the x-axis then the vertical component of velocity is given by which of the following formula?
1) y = x tanθ - gx2/(2vcos2θ)
2) y = x tanθ - gx2/(2v2cosθ)
3) y = x tanθ - gx2/(2vcosθ)
4) y = x tanθ - gx2/(2v2cos2θ)
Correct Answer: y = x tanθ - gx2/(2v2cos2θ)
QID : 105 - What is the Moment of Inertia of a thin circular disc of mass 'M' and radius 'R' about an axis perpendicular to its plane and passing through its centre?
1) MR2/4
2) MR2/3
3) MR2/2
4) MR2/6
Correct Answer: MR2/2
QID : 106 - The expression 'Fv' represents ___________________.
1) Torque
2) Power
3) Work
4) Angular momentum
Correct Answer: Power
QID : 107 - The unit of Gravitational potential energy is?
1) Nm
2) Nm/s
3) kgm
4) kgm/s2
Correct Answer: Nm
QID : 108 - Young's Modulus equals?
1) (F∆l)/(A x L)
2) FL/(A x ∆l)
3) (A x ∆l)/FL
4) (A x L)/(F∆l)
Correct Answer: FL/(A x ∆l)
QID : 109 - Which of the following has the lowest relative density at STP?
1) Hg
2) C2H5OH
3) Water at 4 oC
4) Al
Correct Answer: Hg
QID : 110 - The density of water at __________ K is 1.0 × 103 kg m-3.
1) 4
2) -4
3) 0
4) 277
Correct Answer: 277
QID : 111 - The restriction on application of Bernoulli theorem is that the fluids ______________.
1) should have high viscosity
2) be of unit density
3) must be incompressible
4) be at atmospheric pressure
Correct Answer: must be incompressible
QID : 112 - The principle behind the ________________ is seen in the carburetor where the fuel is sucked into the chamber.
1) barometer
2) manometer
3) vacuum gauge
4) Venturi-meter
Correct Answer: Venturi-meter
QID : 113 - The unit of angular speed is?
1) rad s-1
2) ms-2
3) cms-2
4) ms-1
Correct Answer: rad s-1
QID : 114 - The escape speed from the surface of the Earth is equal to?
1) √(gRE)
2) 2gRE2
3) gRE2
4) √(2gRE)
Correct Answer: √(2gRE)
QID : 115 - If a car decelerates at the rate of 6 m/s2 to come to a stop in 1.25 seconds, then at what speed (in m/s) was the car travelling before it started to decelerate?
1) 9.375
2) 45
3) 4.8
4) 7.5
Correct Answer: 7.5
QID : 116 - A cannon ball is fired at an angle of 15o with the horizontal. If it lands 45m from the cannon (on horizontal ground), then at what speed (in m/s) did it exit from the muzzle? (use g = 10m/s2)
1) 20
2) 30
3) 10
4) 40
Correct Answer: 30
QID : 117 - In the relation, stress = k x strain, k is __________________.
1) spring constant
2) relative density
3) modulus of elasticity
4) factor of plasticity
Correct Answer: modulus of elasticity
QID : 118 - What is the moment of inertia of a rod of mass 'M', length 'L' about an axis perpendicular to it through one end?
1) ML2/2
2) ML2/4
3) ML2/3
4) ML2/6
Correct Answer: ML2/3
QID : 119 - If the acceleration due to gravity is 12.6 m/s2 on a planet of 1/7th the mass of earth, then what must be its radius as compared to 'R', the radius of earth?
1) R/2
2) R/3
3) 3R/2
4) 2R/3
Correct Answer: R/3
QID : 120 - Water flows into a pipe of diameter 7 cm at 20 km/hr and exits through 'n' number of holes each of diameter 1 cm from the other end at 70 km/hr. Find 'n'.
1) 14
2) 7
3) 21
4) 28
Correct Answer: 14
QID : 121 - The SI unit of heat energy is?
1) J
2) C
3) H
4) Q
Correct Answer: J
QID : 122 - Which variable is held constant in Boyle's Law?
1) Pressure
2) Temperature
3) Volume
4) Heat
Correct Answer: Temperature
QID : 123 - Which type of gases obey Boyle’s law and Charles’ law?
1) Low specific heat capacity
2) Low Pressure
3) Low temperature
4) Low density
Correct Answer: Low density
QID : 124 - The amount of heat absorbed or rejected by a substance of mass 'm' and specific heat capacity 's', when it undergoes a temperature change 'ΔT' is equal to?
1) sm/ΔT
2) smΔT
3) mΔT/s
4) sΔT/m
Correct Answer: smΔT
QID : 125 - Which of the following is a path function in thermodynamics?
1) Work
2) density
3) internal energy
4) enthalpy
Correct Answer: Work
QID : 126 - In isobaric processes, the ___________ is constant.
1) mass
2) volume
3) pressure
4) temperature
Correct Answer: pressure
QID : 127 - For a refrigerator the heat extracted from the reservoir is equal to? ('α' is the coefficient of performance of a refrigerator, 'Q1' is the heat released to the hot reservoir, and 'W' is the work done on the system–the refrigerant.)
1) (1+α)/Q1
2) Q1/(1+α)
3) (1+α)/(αQ1)
4) αQ1/(1+α)
Correct Answer: αQ1/(1+α)
QID : 128 - Which of the following is an intensive variable?
1) Internal energy
2) Volume
3) Pressure
4) Mass
Correct Answer: Pressure
QID : 129 - If the diatomic molecule is not rigid but has in addition a vibrational mode, then the total internal energy of a mole of such a gas is?
1) 7RT/2
2) 5RT/2
3) 3RT/2
4) RT/2
Correct Answer: 7RT/2
QID : 130 - The number of molecules in 22.4 litres of a gas at S.T.P. is equal to?
1) 6.02 × 1022
2) 2.06 × 1023
3) 6.02 × 1023
4) 2.06 × 1022
Correct Answer: 6.02 × 1023
QID : 131 - If a molecule of mass 'm' and with x-component of velocity 'vx' collides elastically with a wall of a container then the change in momentum of the molecule is _____________.
1) 2mvx
2) -mvx
3) -2mvx
4) mvx
Correct Answer: -2mvx
QID : 132 - The average kinetic energy of a molecule is dependent on?
1) its pressure
2) its volume
3) the nature of the gas
4) its absolute temperature
Correct Answer: its absolute temperature
QID : 133 - If the length of a 0.2m long aluminium rod expands by 0.5mm on increasing its temperature by 100oC, then find its Coefficient of linear expansion (in 10-5 K-1)?
1) 1
2) 25
3) 2.5
4) 10
Correct Answer: 2.5
QID : 134 - Molecules of Oxygen have how many degrees of freedom? (Assume molecules are rigid)
1) four
2) three
3) five
4) two
Correct Answer: five
QID : 135 -
The total internal energy of a mole of a rigid diatomic gas is?
1) 3RT/2
2) RT/2
3) 5RT/2
4) 7RT/2
Correct Answer: 5RT/2
QID : 136 - 273.15 Kelvin equals?
1) -32o F
2) -273.15o C
3) 273.15o C
4) 32o F
Correct Answer: 32o F
QID : 137 - If the temperature of 10g of mercury (of specific heat capacity 140 Jkg-1K-1) is to be raised from 0oC to 100oC then how much heat (in J) is required?
1) 1400
2) 1.4 x 104
3) 1.4 x 105
4) 140
Correct Answer: 140
QID : 138 - If the r.m.s. velocities of the molecules of two gases 'A' (at 500K) and 'B' (at 300K) are 500m/s and 100m/s respectively, then find molecular mass of the 'B' if molecular mass of 'A' is 2?
1) 15
2) 60
3) 30
4) 12
Correct Answer: 30
QID : 139 - If the volume of a gas at 127oC doubles then what will be the final temperature (inoC), if pressure remains unchanged?
1) 327
2) 527
3) 800
4) 600
Correct Answer: 527
QID : 140 - Calculate the coefficient of performance of a refrigerator if it extracts 1200J of heat from the cold reservoir and releases 1800J of heat to the hot reservoir in each cycle?
1) 2
2) 3
3) 0.5
4) 1
Correct Answer: 2
QID : 141 - The reciprocal of the smallest interval of time after which the motion is repeated is its _____________.
1) phase
2) period
3) frequency
4) span
Correct Answer: frequency
QID : 142 - Which of the following is not a periodic function?
1) esin(ωt + φ)
2) √2sin (ωt + /4)
3) A sin ωt + B cos ωt
4) sin ωt + cos 2 ωt + sin 4 ωt
Correct Answer: esin(ωt + φ)
QID : 143 - The velocity of a particle performing simple harmonic motion is ____________ whose displacement is f(t) = A cos(ωt + φ).
1) ωA sin(ωt + φ )
2) –ωA cos(ωt + φ )
3) –ωA sin(ωt + φ)
4) ωA cos(ωt + φ )
Correct Answer: –ωA sin(ωt + φ)
QID : 144 - The potential energy of a particle performing simple harmonic motion is ____________ whose displacement is f(t) = A cos(ωt + φ).
1) (1/2) mωA2cos2(ωt + φ)
2) (1/2) mω2Acos2(ωt + φ)
3) (1/2) mω2A2cos(ωt + φ)
4) (1/2) mω2A2cos2(ωt + φ)
Correct Answer: (1/2) mω2A2cos2(ωt + φ)
QID : 145 - The angular frequency of the damped oscillator 'ω' is is equal to __________. (Where 'k' is spring constant, 'b' is damping constant and 'm' is mass of the particle)
1) √[k/m - b/(4m2)]
2) √[k/m - b2/(m2)]
3) √[k/m - b/(m2)]
4) √[k/m - b2/(4m2)]
Correct Answer: √[k/m - b2/(4m2)]
QID : 146 - Seismic waves are examples of _____________ waves.
1) Mechanical
2) Matter
3) Electromagnetic
4) Harmonic
Correct Answer: Mechanical
QID : 147 - The speed of longitudinal waves in a medium is given by v = √(X/ρ) where 'ρ' is density of the medium and the unknown term 'X' is?
1) linear mass density
2) Young's Modulus of the medium
3) Bulk Modulus of the medium
4) Density of the gas
Correct Answer: Bulk Modulus of the medium
QID : 148 - When the speed 'v' of a longitudinal wave in an ideal gas of pressure 'P' and density 'ρ' is expressed as v = √(γP/ρ). Here the value of 'γ' is taken as _______ for air.
1) 5/3
2) 7/5
3) 5/7
4) 3/5
Correct Answer: 7/5
QID : 149 - The gap between a consecutive node and anti-node in a stationary wave is?
1) λ/2
2) λ
3) 2λ
4) λ/4
Correct Answer: λ/4
QID : 150 - In a standing wave in a pipe open at both ends the second harmonic has__________.
1) 3 nodes and 2 anti-nodes
2) 2 nodes and 3 anti-nodes
3) 2 nodes and 2 anti-nodes
4) 3 nodes and 3 anti-nodes
Correct Answer: 2 nodes and 3 anti-nodes
Study Kit for SSC Scientific Assistant (IMD) Examination
QID : 151 - The refractive index of the material of a thin prism is equal to? ('A' is angle of the prism and 'Dm' is angle of minimum deviation)
1) 1 + Dm/A
2) 1 - Dm/A
3) 1 + A/Dm
4) 1 - A/Dm
Correct Answer: 1 + Dm/A
QID : 152 - A ray through the centre of curvature incident on a concave mirror after reflection _______________.
1) passes through the focus
2) becomes parallel to the principal axis
3) deviates in such a way that when projected backwards passes through the focus
4) retraces the path it came from
Correct Answer: retraces the path it came from
QID : 153 - If the object is beyond the centre of curvature then the image obtained after reflection from a concave mirror is?
1) beyond the centre of curvature, enlarged, real and inverted
2) between focus and centre of curvature, enlarged, real and inverted
3) beyond the centre of curvature, diminished, real and inverted
4) between focus and centre of curvature, diminished, real and inverted
Correct Answer: between focus and centre of curvature, diminished, real and inverted
QID : 154 - Violet light emerges at an angle of _____ related to the incoming sunlight in case of a primary rainbow.
1) 42o
2) 40o
3) 53o
4) 50o
Correct Answer: 40o
QID : 155 - The linear magnification 'm', for the image formed by a simple microscope is equal to? ('v' is image distance, 'f' is focal length and 'u' is object distance)
1) 1 + v/f
2) 1 - v/f
3) 1 - f/v
4) 1 + f/v
Correct Answer: 1 - v/f
QID : 156 - The energy of the wave travels in a direction _________________ to the wavefront.
1) tangential
2) parallel
3) lateral
4) perpendicular
Correct Answer: perpendicular
QID : 157 - If a plane wavefront is incident on a concave mirror, then the emergent wavefront will be ______________________of the mirror as its centre.
1) spherical with centre of the curvature of the surface
2) conical with focus
3) conical with centre of the curvature of the surface
4) spherical with focus
Correct Answer: spherical with focus
QID : 158 - Experimental observation in a single slit experiment show that the intensity has a central maximum at θ = 0 and other secondary maxima at θ = ______________. (where 'θ' is the angle between the central line and the line joining the midpoint of the slit of width 'a' to any point 'P' on the screen, 'λ' is the wavelength of the light and where n = ±1, ±2, ±3, ....)
1) (n+1/2) λ/a
2) nλ/a
3) (n+1/2)a/λ
4) na/λ
Correct Answer: (n+1/2) λ/a
QID : 159 - Find the angle of a thin prism if its minimum angle of deviation is 2o and its refractive index is 1.5?
1) 4o
2) 3o
3) 3.5o
4) 0.5o
Correct Answer: 4o
QID : 160 -
1) 40
2) 50
3) 25
4) 30
Correct Answer: 50
QID : 161 -
1) 0.375
2) 0.125
3) 0.433
4) 0.667
Correct Answer: 0.375
QID : 162 - In an electric field 'E' directed upwards, an electron of charge 'e' will experience a _______________________.
1) downward force of magnitude eE
2) upward force of magnitude eE
3) downward force of magnitude e/E
4) upward force of magnitude e/E
Correct Answer: downward force of magnitude eE
QID : 163 - The magnitude of electric field of a dipole at a point on the equatorial plane is _____________, where 'p' is the dipole moment and 'r' is the distance of the point from the centre of the dipole and where '2a' is the distance between the two charges.
1) -qar/[2πεo(r2+a2)3/2]
2) -qa/[2πεo(r2+a2)2]
3) -qar/[2πεo(r2+a2)2]
4) -qa/[2πεo(r2+a2)3/2]
Correct Answer: -qa/[2πεo(r2+a2)3/2]
QID : 164 - Electrostatic potential at a distance 'r' from a point charge 'q' is proportional to?
1) 1/r
2) 1/r2
3) r
4) r2
Correct Answer: 1/r
QID : 165 - The charges 'q1' and q2 produce a potential 'V1,2', which at any point 'P' is given by ________________.
1) 1/(4πεo) x (q12/r1P + q22/r2P)
2) 1/(4πεo) x (q1/r1P2 + q2/r2P2)
3) 1/(4πεo) x (q1/r1P + q2/r2P)
4) 1/(4πεo) x (q12/r1P2 + q22/r2P2)
Correct Answer: 1/(4πεo) x (q1/r1P + q2/r2P)
QID : 166 - Which of the following results regarding electrostatics of conductors is not true?
1) At the surface of a charged conductor, electrostatic field must be
tangential to the surface at every point.
2) Inside a conductor, electrostatic field is zero.
3) The interior of a conductor can have no excess charge in the static
situation.
4) Electrostatic potential is constant throughout the volume of the conductor
and has the same value (as inside) on its surface.
Correct Answer: At the surface of a charged conductor, electrostatic field must be tangential to the surface at every point.
QID : 167 - In the inner region between the two charged plates of a parallel plate capacitor the electric field is equal to ____________. ('Q' is magnitude of charge on each plate of area 'A')
1) εo/AQ
2) Q/(εoA)
3) A/(εoQ)
4) QA/εo
Correct Answer: Q/(εoA)
QID : 168 - The work done in charging a capacitor is equal to? ('Q' is magnitude of charge on each plate of the capacitor between which the potential difference is 'V')
1) V2/2Q
2) Q/2V
3) QV/2
4) V2/Q
Correct Answer: QV/2
QID : 169 - If two resistors of 10 kΩ and 30 kΩ are connected in parallel what will be the value of the effective resistance (in kΩ)?
1) 10
2) 12.5
3) 7.5
4) 5
Correct Answer: 7.5
QID : 170 - While studying electron drift through a metallic conductor, current per unit area called current density is equal to? (Where 'e' is charge on an electron, 'm' is mass of an electron, 'E' is the electric field, 'τ' is relaxation time and 'n' is the number of free electrons per unit volume)
1) ne2/m
2) ne2τ/m
3) eτ/m
4) ne2τE/m
Correct Answer: ne2τE/m
QID : 171 - The force on a particle carrying a charge 'q' and moving with a velocity 'v' perpendicular to a uniform magnetic field 'B' is given by _________.
1) q2v/B
2) qvB
3) v2B/q
4) qv/B
Correct Answer: qvB
QID : 172 - The velocity of the particle of mass 'm' carrying a charge 'q' that exits the cyclotron is equal to? (Where 'R' is radius of the trajectory at exit and 'B' is the magnetic field perpendicular to the Dees)
1) qBR/m
2) qBm/R
3) BRm/q
4) qmR/B
Correct Answer: qBR/m
QID : 173 - The magnetic moment (m) of a current loop = _________. ('I' is the current in the loop and 'A' is the area of the rectangular loop)
1) I/A
2) IA
3) A/I
4) I2A
Correct Answer: IA
QID : 174 - The axis of the magnetic dipole of earth does not coincide with the axis of rotation of the earth but is presently titled by approximately ________ with respect to the later.
1) 1.3o
2) 6.3o
3) 11.3o
4) 16.3o
Correct Answer: 11.3o
QID : 175 - If the interior of the solenoid is filled with a material with non-zero magnetisation the net field in the interior of the solenoid may be expressed as B = _____________.
1) (Bo + Bm)/2
2) √(Bo + Bm)
3) Bo + Bm
4) √[(Bo + Bm)/2]
Correct Answer: Bo + Bm
QID : 176 - Diamagnetic substances are those which have tendency to move from ___________________________________ by a magnet.
1) stronger to the weaker part of the external magnetic field and it would be
repelled
2) stronger to the weaker part of the external magnetic field and it would be
attracted
3) weaker to the stronger part of the external magnetic field and it would be
repelled
4) weaker to the stronger part of the external magnetic field and it would be
attracted
Correct Answer: stronger to the weaker part of the external magnetic field and it would be repelled
QID : 177 - The root mean square (rms) current = __________. (Where 'im' amplitude of the AC current)
1) im/2
2) √2 im
3) im/√2
4) 2 im
Correct Answer: im/√2
QID : 178 - For a series RLC circuit driven by voltage v = vmsinωt, the current is given by i = im sin(ωt + φ), the average power loss over a complete cycle is given by 'P' = _________.
1) V I tanφ
2) V I cos2φ
3) V I tan2φ
4) V I cosφ
Correct Answer: V I cosφ
QID : 179 - The equation ∮B.dA = 0 represents ____________.
1) Gauss’s Law for electricity
2) Faraday’s Law
3) Gauss’s Law for magnetism
4) Ampere – Maxwell Law
Correct Answer: Gauss’s Law for magnetism
QID : 180 - The wavelengths of which electromagnetic waves is between those of ultraviolet light and gamma rays?
1) Radio waves
2) X-Rays
3) Microwaves
4) Infra-red light
Correct Answer: X-Rays
QID : 181 -
1) A-1, B-3, C-2
2) A-3, B-2, C-1
3) A-3, B-1, C-2
4) A-2, B-3, C-1
Correct Answer: A-2, B-3, C-1
QID : 182 - The empirical formula for the observed wavelengths (λ) for hydrogen is 1/λ = R(1/k2 - 1/n2), where 'R' is Rydberg constant. For the Balmer series the value of 'k' is?
1) 3
2) 2
3) 4
4) 1
Correct Answer: 2
QID : 183 - The magnitude of Planck's constant is 6.6x10-34, and its unit is _________.
1) Js
2) J/s
3) Js2
4) J/s2
Correct Answer: Js
QID : 184 - If the energy of the electron in the 1st orbit of hydrogen is -13.6 eV, then how much is the energy (in eV) of an electron in the 3rd orbit?
1) -1.51
2) -4.53
3) -40.8
4) -122.4
Correct Answer: -1.51
QID : 185 - According to classical electromagnetic theory, an accelerating charged particle emits radiation in the form of electromagnetic waves. The energy of an accelerating electron should therefore, ____________________.
1) continuously increase
2) continuously decrease
3) take random values
4) be always constant
Correct Answer: continuously decrease
QID : 186 - Calculate the wavelength (in nm) of the spectral line of Lyman series for n = 3. (Rydberg constant = 1.1 x 107 m-1)
1) 202
2) 302
3) 102
4) 402
Correct Answer: 102
QID : 187 - Nucleus of 233U92 emits which particles to give nucleus of 225Ra88?
1) 2β
2) 2α
3) 2α, 2β
4) 1α, 2β
Correct Answer: 2α
QID : 188 - 237Np93 → AU92 + α particle + β particle. What is the value of A?
1) 234
2) 231
3) 233
4) 235
Correct Answer: 233
QID : 189 - 40Ar18 and 38Ar18 are examples of?
1) isotopes
2) isobars
3) isomers
4) isotones
Correct Answer: isotopes
QID : 190 - In about 5 billion years the sun’s core will be largely consisting of ____________.
1) helium
2) lithium
3) hydrogen
4) protons
Correct Answer: helium
QID : 191 - An atom of 106Pd46 has how many neutrons?
1) 60
2) 106
3) 46
4) 76
Correct Answer: 60
QID : 192 - Half life of Sodium-24 is 15 hours. How much Sodium (in gm) will be left out of 0.25gm after 30 hours?
1) 0.125
2) 0.03125
3) 0.0625
4) 0.015625
Correct Answer: 0.0625
QID : 193 - 1no + 235U92 → yCs55 + 90Rb37 + 21no. Find 'y' from the given fission equation of an uranium nucleus?
1) 142
2) 143
3) 144
4) 145
Correct Answer: 144
QID : 194 - 3He2 + 3He2 → 4He2 + 2 ___________
1) Positrons
2) Protons
3) Neutrons
4) Electrons
Correct Answer: Protons
QID : 195 - Calculate the mass defect in (in u) an atom of of 4He2 atomic mass 4.002602 u. (masses of neutron, proton and electron are 1.00866 u, 1.00727 u and 0.00055 u respectively).
1) 0.030357
2) 0.060715
3) 0.091073
4) 0.015178
Correct Answer: 0.030357
QID : 196 - In ______________there is a large gap between the conduction band and the valence band.
1) insulators
2) metallic conductors
3) elemental semiconductors
4) compound semiconductors
Correct Answer: insulators
QID : 197 - When a diode is forward biased, then the depletion layer width __________________________.
1) increases and the barrier height is reduced
2) decreases and the barrier height is reduced
3) decreases and the barrier height is raised
4) increases and the barrier height is raised
Correct Answer: decreases and the barrier height is reduced
QID : 198 - In a transistor the ___________ is very thin and lightly doped.
1) emitter
2) base
3) junction
4) collector
Correct Answer: base
QID : 199 - When a transistor is used in common emitter configuration, the variation of the ________________ voltage is called the output characteristic.
1) base current with the collector-emitter
2) collector current with the base-emitter
3) base current with the collector-base
4) collector current with the collector-emitter
Correct Answer: collector current with the collector-emitter
QID : 200 - The output of an AND gate is 1 if the inputs are _______.
1) (0,0)
2) (1,1)
3) (0,1)
4) (1,0)
Correct Answer: (1,1)
