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MCQOPTIONS
This section includes 12583 Mcqs, each offering curated multiple-choice questions to sharpen your Joint Entrance Exam - Main (JEE Main) knowledge and support exam preparation. Choose a topic below to get started.
| 9051. |
Assertion : Electromagnets are made of soft iron. Reason : Coercivity of soft iron is small. |
| A. | If both assertion and reason are true and the reason is the correct explanation of the assertion. |
| B. | If both assertion and reason are true but reason is not the correct explanation of the assertion. |
| C. | If assertion is true but reason is false. |
| D. | If the assertion and reason both are false. |
| E. | If assertion is false but reason is true. |
| Answer» B. If both assertion and reason are true but reason is not the correct explanation of the assertion. | |
| 9052. |
An ac source is connected to a resistive circuits. Which of the following is true [CPMT 1985] |
| A. | Current leads the voltage and both are in same phase |
| B. | Current lags behind the voltage and both are in same phase |
| C. | Current and voltage are in same phase |
| D. | Any of the above may be true depending upon the value of resistance |
| Answer» D. Any of the above may be true depending upon the value of resistance | |
| 9053. |
Assertion : In extreme position of a particle executing S.H.M., both velocity and acceleration are zero. Reason : In S.H.M., acceleration always acts towards mean position. |
| A. | If both assertion and reason are true and the reason is the correct explanation of the assertion. |
| B. | If both assertion and reason are true but reason is not the correct explanation of the assertion. |
| C. | If assertion is true but reason is false. |
| D. | If the assertion and reason both are false. |
| E. | If assertion is false but reason is true. |
| Answer» F. | |
| 9054. |
Assertion : If q be the angle between \[\vec{A}\] and \[\vec{B}\], then \[\tan \theta =\frac{\vec{A}\times \vec{B}}{\vec{A}.\vec{B}}\] Reason : \[\vec{A}\times \vec{B}\] is perpendicular to \[\vec{A}.\vec{B}\] |
| A. | If both assertion and reason are true and the reason is the correct explanation of the assertion. |
| B. | If both assertion and reason are true but reason is not the correct explanation of the assertion. |
| C. | If assertion is true but reason is false. |
| D. | If the assertion and reason both are false. |
| E. | If assertion is false but reason is true. |
| Answer» E. If assertion is false but reason is true. | |
| 9055. |
Assertion : The speed of revolution of an artificial satellite revolving very near the earth is \[8\,km{{s}^{-1}}\]. Reason : Orbital velocity of a satellite, become independent of height of near satellite. |
| A. | If both assertion and reason are true and the reason is the correct explanation of the assertion. |
| B. | If both assertion and reason are true but reason is not the correct explanation of the assertion. |
| C. | If assertion is true but reason is false. |
| D. | If the assertion and reason both are false. |
| E. | If assertion is false but reason is true. |
| Answer» B. If both assertion and reason are true but reason is not the correct explanation of the assertion. | |
| 9056. |
What should be the angular speed of earth, so that body lying on equator may appear weightlessness \[(g=10\,m/{{s}^{2}},\,\,R=6400\,km)\] [Pb. PET 2000] |
| A. | \[\frac{1}{800}rad/s\] |
| B. | \[\frac{1}{400}rad/s\] |
| C. | \[\frac{1}{600}rad/s\] |
| D. | \[\frac{1}{100}rad/s\] |
| Answer» B. \[\frac{1}{400}rad/s\] | |
| 9057. |
A neutral point is obtained at the centre of a vertical circular coil carrying current. The angle between the plane of the coil and the magnetic meridian is [SCRA 1998] |
| A. | 0 |
| B. | 45° |
| C. | 60° |
| D. | 90° |
| Answer» E. | |
| 9058. |
In the spectrum of hydrogen atom, the ratio of the longest wavelength in Lyman series to the longest wavelength in the Balmer series is [UPSEAT 2004] |
| A. | 5/27 |
| B. | 1/93 |
| C. | 4/9 |
| D. | 3/2 |
| Answer» B. 1/93 | |
| 9059. |
Assertion : Angle of repose is equal to angle of limiting friction. Reason : When the body is just at the point of motion, the force of friction in this stage is called as limiting friction. |
| A. | If both assertion and reason are true and the reason is the correct explanation of the assertion. |
| B. | If both assertion and reason are true but reason is not the correct explanation of the assertion. |
| C. | If assertion is true but reason is false. |
| D. | If the assertion and reason both are false. |
| E. | If assertion is false but reason is true. |
| Answer» C. If assertion is true but reason is false. | |
| 9060. |
Assertion : When temperature of cold junction of a thermocouple is lowered, the value of neutral temperature of this thermocouple is raised. Reason : When the difference of temperature of two junction is raised, more thermo e.m.f. is produced. |
| A. | If both assertion and reason are true and the reason is the correct explanation of the assertion. |
| B. | If both assertion and reason are true but reason is not the correct explanation of the assertion. |
| C. | If assertion is true but reason is false. |
| D. | If the assertion and reason both are false. |
| E. | If assertion is false but reason is true. |
| Answer» E. If assertion is false but reason is true. | |
| 9061. |
A block of mass 100 gm slides on a rough horizontal surface. If the speed of the block decreases from 10 m/s to 5 m/s, the thermal energy developed in the process is [UPSEAT 2002] |
| A. | 3.75 J |
| B. | 37.5 J |
| C. | 0.375 J |
| D. | 0.75 J |
| Answer» B. 37.5 J | |
| 9062. |
Which of the following do not require medium for transmission [RPMT 2000] |
| A. | Cathode ray |
| B. | Electromagnetic wave |
| C. | Sound wave |
| D. | None of the above |
| Answer» C. Sound wave | |
| 9063. |
The ratio of longest wavelength and the shortest wavelength observed in the five spectral series of emission spectrum of hydrogen is [MP PET 1999] |
| A. | \[\frac{4}{3}\] |
| B. | \[\frac{525}{376}\] |
| C. | 25 |
| D. | \[\frac{900}{11}\] |
| Answer» E. | |
| 9064. |
A medium can carry a longitudinal wave because it has the property of [KCET 1994] |
| A. | Mass |
| B. | Density |
| C. | Compressibility |
| D. | Elasticity |
| Answer» E. | |
| 9065. |
An oxide coated filament is useful in vacuum tubes because essentially [SCRA 1994] |
| A. | It has high melting point |
| B. | It can withstand high temperatures |
| C. | It has good machanical strength |
| D. | It can emit electrons at relatively lower temperatures |
| Answer» E. | |
| 9066. |
Read the assertion and reason carefully to mark the correct option out of the options given below: Assertion : A person working on a horizontal road with a load on his head does no work. Reason : No work is said to be done, if directions of force and displacement of load are perpendicular to each other. |
| A. | If both assertion and reason are true and the reason is the correct explanation of the assertion. |
| B. | If both assertion and reason are true but reason is not the correct explanation of the assertion. |
| C. | If assertion is true but reason is false. |
| D. | If the assertion and reason both are false. |
| E. | If assertion is false but reason is true. |
| Answer» B. If both assertion and reason are true but reason is not the correct explanation of the assertion. | |
| 9067. |
540 g of ice at 0°C is mixed with 540 g of water at 80°C. The final temperature of the mixture is [AFMC 1994] |
| A. | 0°C |
| B. | 40°C |
| C. | 80°C |
| D. | Less than 0°C |
| Answer» B. 40°C | |
| 9068. |
An electron of charge ?e? coulomb passes through a potential difference of \[V\] volts. Its energy in ?joules? will be [MP PET 2000] |
| A. | \[V/e\] |
| B. | eV |
| C. | \[e/V\] |
| D. | V |
| Answer» C. \[e/V\] | |
| 9069. |
The magnetic field due to a current carrying circular loop of radius 3 cm at a point on the axis at a distance of 4 cm from the centre is 54 mT. What will be its value at the centre of the loop [AIEEE 2004] |
| A. | 250 m T |
| B. | 150 m T |
| C. | 125 m T |
| D. | 75 m T |
| Answer» B. 150 m T | |
| 9070. |
Assertion : All black coloured objects are considered black bodies. Reason : Black colour is a good absorber of heat. |
| A. | If both assertion and reason are true and the reason is the correct explanation of the assertion. |
| B. | If both assertion and reason are true but reason is not the correct explanation of the assertion. |
| C. | If assertion is true but reason is false. |
| D. | If the assertion and reason both are false. |
| E. | If assertion is false but reason is true. |
| Answer» F. | |
| 9071. |
An unknown frequency x produces 8 beats per seconds with a frequency of 250 Hz and 12 beats with 270 Hz source, then x is [CPMT 1997; KCET 2000] |
| A. | 258 Hz |
| B. | 242 Hz |
| C. | 262 Hz |
| D. | 282 Hz |
| Answer» B. 242 Hz | |
| 9072. |
Assertion : Density of all the nuclei is same. Reason : Radius of nucleus is directly proportional to the cube root of mass number. [AIIMS 2000] |
| A. | If both assertion and reason are true and the reason is the correct explanation of the assertion. |
| B. | If both assertion and reason are true but reason is not the correct explanation of the assertion. |
| C. | If assertion is true but reason is false. |
| D. | If the assertion and reason both are false. |
| E. | If assertion is false but reason is true. |
| Answer» B. If both assertion and reason are true but reason is not the correct explanation of the assertion. | |
| 9073. |
Assertion : The force with which one plate of a parallel plate capacitor is attracted towards the other plate is equal to square of surface density per e per unit area. Reason : The electric field due to one charged plate of the capacitor at the location of the other is equal to surface density per e. |
| A. | If both assertion and reason are true and the reason is the correct explanation of the assertion. |
| B. | If both assertion and reason are true but reason is not the correct explanation of the assertion. |
| C. | If assertion is true but reason is false. |
| D. | If the assertion and reason both are false. |
| E. | If assertion is false but reason is true. |
| Answer» E. If assertion is false but reason is true. | |
| 9074. |
Assertion : When radius of circular loop carrying current is doubled, its magnetic moment becomes four times. Reason : Magnetic moment depends on area of the loop. |
| A. | If both assertion and reason are true and the reason is the correct explanation of the assertion. |
| B. | If both assertion and reason are true but reason is not the correct explanation of the assertion. |
| C. | If assertion is true but reason is false. |
| D. | If the assertion and reason both are false. |
| E. | If assertion is false but reason is true. |
| Answer» C. If assertion is true but reason is false. | |
| 9075. |
AM is used for broadcasting because |
| A. | It is more noise immune than other modulation systems |
| B. | It requires less transmitting power compared with other systems |
| C. | Its use avoids receiver complexity |
| D. | No other modulation system can provide the necessary bandwidth faithful transmission |
| Answer» D. No other modulation system can provide the necessary bandwidth faithful transmission | |
| 9076. |
If the earth suddenly shrinks (without changing mass) to half of its present radius, the acceleration due to gravity will be [MNR 1998] |
| A. | g/2 |
| B. | 4g |
| C. | g/4 |
| D. | 2g |
| Answer» C. g/4 | |
| 9077. |
To explain his theory, Bohr used [CBSE PMT1993; MP PET 2002] |
| A. | Conservation of linear momentum |
| B. | Conservation of angular momentum |
| C. | Conservation of quantum frequency |
| D. | Conservation of energy |
| Answer» C. Conservation of quantum frequency | |
| 9078. |
Assertion : Mass and energy are not conserved separately, but are conserved as a single entity called mass-energy. Reason : Mass and energy conservation can be obtained by Einstein equation for energy. |
| A. | If both assertion and reason are true and the reason is the correct explanation of the assertion. |
| B. | If both assertion and reason are true but reason is not the correct explanation of the assertion. |
| C. | If assertion is true but reason is false. |
| D. | If the assertion and reason both are false. |
| E. | If assertion is false but reason is true. |
| Answer» B. If both assertion and reason are true but reason is not the correct explanation of the assertion. | |
| 9079. |
Dry ice is [CPMT 2000] |
| A. | Ice cube |
| B. | Sodium chloride |
| C. | Liquid nitrogen |
| D. | Solid carbon dioxide |
| Answer» E. | |
| 9080. |
In hydrogen atom, an electron is revolving in the orbit of radius \[0.53\,{AA}\] with \[6.6\times {{10}^{15}}\]rotations/second. Magnetic field produced at the centre of the orbit is [MP PET 2003] |
| A. | \[0.125\,wb/{{m}^{2}}\] |
| B. | \[1.25\,wb/{{m}^{2}}\] |
| C. | \[12.5\,wb/{{m}^{2}}\] |
| D. | \[125\,wb/{{m}^{2}}\] |
| Answer» D. \[125\,wb/{{m}^{2}}\] | |
| 9081. |
Assertion : The capacity of a given conductor remains same even if charge is varied on it. Reason : Capacitance depends upon nearly medium as well as size and shape of conductor. |
| A. | If both assertion and reason are true and the reason is the correct explanation of the assertion. |
| B. | If both assertion and reason are true but reason is not the correct explanation of the assertion. |
| C. | If assertion is true but reason is false. |
| D. | If the assertion and reason both are false. |
| E. | If assertion is false but reason is true. |
| Answer» B. If both assertion and reason are true but reason is not the correct explanation of the assertion. | |
| 9082. |
A water fall is 84 metres high. If half of the potential energy of the falling water gets converted to heat, the rise in temperature of water will be [JIPMER 2002] |
| A. | 0.098°C |
| B. | 0.98°C |
| C. | 9.8°C |
| D. | 0.0098°C |
| Answer» B. 0.98°C | |
| 9083. |
Assertion : In circular motion, work done by centripetal force is zero. Reason : In circular motion centripetal force is perpendicular to the displacement. |
| A. | If both assertion and reason are true and the reason is the correct explanation of the assertion. |
| B. | If both assertion and reason are true but reason is not the correct explanation of the assertion. |
| C. | If assertion is true but reason is false. |
| D. | If the assertion and reason both are false. |
| E. | If assertion is false but reason is true. |
| Answer» B. If both assertion and reason are true but reason is not the correct explanation of the assertion. | |
| 9084. |
Energy of an electron in an excited hydrogen atom is ? 3.4 eV. Its angular momentum will be: \[h=6.626\times {{10}^{-34}}J-s\] [UPSEAT 1999; Kerala PET 2002] |
| A. | \[1.11\times {{10}^{34}}J\ \sec \] |
| B. | \[1.51\times {{10}^{-31}}J\ \sec \] |
| C. | \[2.11\times {{10}^{-34}}J\ \sec \] |
| D. | \[3.72\times {{10}^{-34}}J\ \sec \] |
| Answer» D. \[3.72\times {{10}^{-34}}J\ \sec \] | |
| 9085. |
Through which mode of propagation, the radio waves can be sent from one place to another [JIPMER 2003] |
| A. | Ground wave propagation |
| B. | Sky wave propagation |
| C. | Space wave propagation |
| D. | All of them |
| Answer» E. | |
| 9086. |
The force between the plates of a parallel plate capacitor of capacitance\[C\] and distance of separation of the plates \[d\] with a potential difference \[V\] between the plates, is [MP PMT 1999] |
| A. | \[\frac{C{{V}^{2}}}{2d}\] |
| B. | \[\frac{{{C}^{2}}{{V}^{2}}}{2{{d}^{2}}}\] |
| C. | \[\frac{{{C}^{2}}{{V}^{2}}}{{{d}^{2}}}\] |
| D. | \[\frac{{{V}^{2}}d}{C}\] |
| Answer» B. \[\frac{{{C}^{2}}{{V}^{2}}}{2{{d}^{2}}}\] | |
| 9087. |
Bohr's atom model assumes [KCET 2005] |
| A. | The nucleus is of infinite mass and is at rest |
| B. | Electrons in a quantized orbit will not radiate energy |
| C. | Mass of electron remains constant |
| D. | All the above conditions |
| Answer» E. | |
| 9088. |
Power factor is maximum in an LCR circuit when [RPET 2000] |
| A. | \[{{X}_{L}}={{X}_{C}}\] |
| B. | \[R=0\] |
| C. | \[{{X}_{L}}=0\] |
| D. | \[{{X}_{C}}=0\] |
| Answer» B. \[R=0\] | |
| 9089. |
Assertion : The film which appears bright in reflected system will appear dark in the transmitted light and vice-versa. Reason : The conditions for film to appear bright or dark in reflected light are just reverse to those in the transmitted light. |
| A. | If both assertion and reason are true and the reason is the correct explanation of the assertion. |
| B. | If both assertion and reason are true but reason is not the correct explanation of the assertion. |
| C. | If assertion is true but reason is false. |
| D. | If the assertion and reason both are false. |
| E. | If assertion is false but reason is true. |
| Answer» B. If both assertion and reason are true but reason is not the correct explanation of the assertion. | |
| 9090. |
Assertion : For best contrast between maxima and minima in the interference pattern of Young?s double slit experiment, the intensity of light emerging out of the two slits should be equal. Reason : The intensity of interference pattern is proportional to square of amplitude. |
| A. | If both assertion and reason are true and the reason is the correct explanation of the assertion. |
| B. | If both assertion and reason are true but reason is not the correct explanation of the assertion. |
| C. | If assertion is true but reason is false. |
| D. | If the assertion and reason both are false. |
| E. | If assertion is false but reason is true. |
| Answer» C. If assertion is true but reason is false. | |
| 9091. |
Assertion : In Young?s double slit experiment, the fringes become indistinct if one of the slits is covered with cellophane paper. Reason : The cellophane paper decrease the wavelength of light. |
| A. | If both assertion and reason are true and the reason is the correct explanation of the assertion. |
| B. | If both assertion and reason are true but reason is not the correct explanation of the assertion. |
| C. | If assertion is true but reason is false. |
| D. | If the assertion and reason both are false. |
| E. | If assertion is false but reason is true. |
| Answer» D. If the assertion and reason both are false. | |
| 9092. |
A circular loop of radius 0.0157m carries a current of 2.0 amp. The magnetic field at the centre of the loop is \[({{\mu }_{0}}=4\pi \times {{10}^{-7}}\,weber/amp-m)\] [MP PET 2000] |
| A. | \[\text{1}\text{.57}\times \text{10}{{\text{ }}^{\text{-5}}}\,weber/{{m}^{2}}\] |
| B. | \[8.0\times \text{10}{{\text{ }}^{\text{-5}}}\,weber/{{m}^{2}}\] |
| C. | \[2.5\times \text{10}{{\text{ }}^{\text{-5}}}\,weber/{{m}^{2}}\] |
| D. | \[\text{3}.14\times \text{10}{{\text{ }}^{\text{-5}}}\,weber/{{m}^{2}}\] |
| Answer» C. \[2.5\times \text{10}{{\text{ }}^{\text{-5}}}\,weber/{{m}^{2}}\] | |
| 9093. |
Assertion : Water at the foot of the water fall is always at different temperature from that at the top. Reason : The potential energy of water at the top is converted into heat energy during falling. |
| A. | If both assertion and reason are true and the reason is the correct explanation of the assertion. |
| B. | If both assertion and reason are true but reason is not the correct explanation of the assertion. |
| C. | If assertion is true but reason is false. |
| D. | If the assertion and reason both are false. |
| E. | If assertion is false but reason is true. |
| Answer» B. If both assertion and reason are true but reason is not the correct explanation of the assertion. | |
| 9094. |
Assertion : Efficiency of a Carnot engine increase on reducing the temperature of sink. Reason : The efficiency of a Carnot engine is defined as ratio of net mechanical work done per cycle by the gas to the amount of heat energy absorbed per cycle from the source. |
| A. | If both assertion and reason are true and the reason is the correct explanation of the assertion. |
| B. | If both assertion and reason are true but reason is not the correct explanation of the assertion. |
| C. | If assertion is true but reason is false. |
| D. | If the assertion and reason both are false. |
| E. | If assertion is false but reason is true. |
| Answer» C. If assertion is true but reason is false. | |
| 9095. |
Hailstone at 0°C falls from a height of 1 km on an insulating surface converting whole of its kinetic energy into heat. What part of it will melt \[(g=10\,m/{{s}^{2}})\] [MP PMT 1994] |
| A. | \[\frac{1}{33}\] |
| B. | \[\frac{1}{8}\] |
| C. | \[\frac{1}{33}\times {{10}^{-4}}\] |
| D. | All of it will melt |
| Answer» B. \[\frac{1}{8}\] | |
| 9096. |
A battery is connected between two points A and B on the circumference of a uniform conducting ring of radius r and resistance R. One of the arcs AB of the ring subtends an angle \[\theta \] at the centre. The value of the magnetic induction at the centre due to the current in the ring is [IIT 1995] |
| A. | Proportional to \[2\,(180{}^\circ -\theta )\] |
| B. | Inversely proportional to r |
| C. | Zero, only if \[\theta =180{}^\circ \] |
| D. | Zero for all values of \[\theta \] |
| Answer» E. | |
| 9097. |
Which among the following, is a form of energy [DCE 2004] |
| A. | Light |
| B. | Pressure |
| C. | Momentum |
| D. | Power |
| Answer» B. Pressure | |
| 9098. |
10 gm of ice at 0°C is mixed with 100 gm of water at 50°C. What is the resultant temperature of mixture [AFMC 2005] |
| A. | 31.2°C |
| B. | 32.8°C |
| C. | 36.7°C |
| D. | 38.2°C |
| Answer» E. | |
| 9099. |
The thermal capacity of 40 gm of aluminium (specific heat = 0.2 cal/gm/°C) is [CBSE PMT 1990] |
| A. | 40 cal/°C |
| B. | 160 cal/°C |
| C. | 200 cal/°C |
| D. | 8 cal/°C |
| Answer» E. | |
| 9100. |
The dimension of the magnetic field intensity B is [MP PET 2001] |
| A. | \[ML{{T}^{-2}}{{A}^{-1}}\] |
| B. | \[M{{T}^{-2}}{{A}^{-1}}\] |
| C. | \[M{{L}^{2}}T{{A}^{-2}}\] |
| D. | \[{{M}^{2}}L{{T}^{-2}}{{A}^{-1}}\] |
| Answer» C. \[M{{L}^{2}}T{{A}^{-2}}\] | |