MCQOPTIONS
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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.
| 9801. |
Assertion : When the velocity of projection of a body is made n times, its time of flight becomes n times. Reason : Range of projectile does not depend on the initial velocity of a body. |
| 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. | |
| 9802. |
For electroplating a spoon, it is placed in the voltameter at [MP PMT/PET 1998] |
| A. | The position of anode |
| B. | The position of cathode |
| C. | Exactly in the middle of anode and the cathode |
| D. | Anywhere in the electrolyte |
| Answer» C. Exactly in the middle of anode and the cathode | |
| 9803. |
Assertion : Work and heat are two equivalent form of energy. Reason : Work is the transfer of mechanical energy irrespective of temperature difference, whereas heat is the transfer of thermal energy because of temperature difference only. |
| 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. | |
| 9804. |
Assertion : A body having non-zero acceleration can have a constant velocity. Reason : Acceleration is the rate of change of velocity. |
| 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. | |
| 9805. |
If \[|\,\vec{A}+\vec{B}\,|\,=\,|\,\vec{A}\,|+|\,\vec{B}\,|\], then angle between \[\vec{A}\]and \[\vec{B}\] will be [CBSE PMT 2001] |
| A. | \[\text{9}0{}^\circ \] |
| B. | \[\text{12}0{}^\circ \] |
| C. | \[0{}^\circ \] |
| D. | \[\text{6}0{}^\circ \] |
| Answer» D. \[\text{6}0{}^\circ \] | |
| 9806. |
If the Earth losses its gravity, then for a body [BHU 1999; MHCET 2003] |
| A. | Weight becomes zero, but not the mass |
| B. | Mass becomes zero, but not the weight |
| C. | Both mass and weight become zero |
| D. | Neither mass nor weight become zero |
| Answer» B. Mass becomes zero, but not the weight | |
| 9807. |
Assertion : The resistivity of a semiconductor increases with temperature. Reason : The atoms of a semiconductor vibrate with larger amplitude at higher temperatures thereby increasing its resistivity [AIIMS 2003] |
| 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. | |
| 9808. |
Faraday's laws of electrolysis are related to [IIT 1983] |
| A. | The atomic number of positive ion |
| B. | The equivalent weight of electrolyte |
| C. | The atomic number of negative ion |
| D. | The velocity of positive ion |
| Answer» C. The atomic number of negative ion | |
| 9809. |
If a water drop is kept between two glass plates, then its shape is [CPMT 1997] |
| A. | |
| B. | |
| C. | None of these |
| Answer» D. | |
| 9810. |
The value of the current through an inductance of \[1H\] and of negligible resistance, when connected through an ac source of 200 V and 50 Hz, is [AFMC 2000] |
| A. | 0.637 A |
| B. | 1.637 A |
| C. | 2.637A |
| D. | 3.637 A |
| Answer» B. 1.637 A | |
| 9811. |
Assertion : Annihilation of electron and positron is an example of decay of charges. Reason : In the process of annihilation an electron and a positron combine to give a gamma particle. |
| 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. | |
| 9812. |
Given that \[\overrightarrow{A}+\overrightarrow{B}=\overrightarrow{C}\]and that \[\overrightarrow{C}\] is \[\bot \] to \[\overrightarrow{A}\]. Further if \[|\overrightarrow{A}|\,=\,|\overrightarrow{C}|,\]then what is the angle between \[\overrightarrow{A}\] and \[\overrightarrow{B}\] |
| A. | \[\frac{\pi }{4}radian\] |
| B. | \[\frac{\pi }{2}radian\] |
| C. | \[\frac{3\pi }{4}radian\] |
| D. | \[\pi \,\,radian\] |
| Answer» D. \[\pi \,\,radian\] | |
| 9813. |
The magnetic induction at any point due to a long straight wire carrying a current is [MP PMT/PET 1998] |
| A. | Proportional to the distance from the wire |
| B. | Inversely proportional to the distance from wire |
| C. | Inversely proportional to the square of the distance from the wire |
| D. | Does not depend on distance |
| Answer» C. Inversely proportional to the square of the distance from the wire | |
| 9814. |
Assertion : A bullet is fired from a rifle. If the rifle recoils freely, the kinetic energy of rifle is more than that of the bullet. Reason : In the case of rifle bullet system the law of conservation of momentum violates. |
| 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. | |
| 9815. |
The latent heat of vaporization of a substance is always [SCRA 1998] |
| A. | Greater than its latent heat of fusion |
| B. | Greater than its latent heat of sublimation |
| C. | Equal to its latent heat of sublimation |
| D. | Less than its latent heat of fusion |
| Answer» B. Greater than its latent heat of sublimation | |
| 9816. |
Assertion : The illuminance of an image produced by a convex lens is greater in the middle and less towards the edges. Reason : The middle part of image is formed by undeflected rays while outer part by inclined rays. |
| 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. | |
| 9817. |
In a L-R circuit, the value of L is \[\left( \frac{0.4}{\pi } \right)\ henry\] and the value of R is 30 ohm. If in the circuit, an alternating e.m.f. of 200 volt at 50 cycles per sec is connected, the impedance of the circuit and current will be [MP PET 1996; DPMT 2003] |
| A. | \[11.4\,\Omega ,\,17.5\,A\] |
| B. | \[30.7\,\Omega ,\,6.5A\] |
| C. | \[40.4\,\Omega ,\,5\,A\] |
| D. | \[50\,\Omega ,\,4A\] |
| Answer» E. | |
| 9818. |
The magnetic moment of a current carrying loop is \[2.1\times {{10}^{-25}}\,amp\times {{m}^{2}}\]. The magnetic field at a point on its axis at a distance of \[1\,{AA}\] is |
| A. | \[4.2\times {{10}^{-2}}\,weber/{{m}^{2}}\] |
| B. | \[4.2\times {{10}^{-3}}\,weber/{{m}^{2}}\] |
| C. | \[4.2\times {{10}^{-4}}\,weber/{{m}^{2}}\] |
| D. | \[4.2\times {{10}^{-5}}\,weber/{{m}^{2}}\] |
| Answer» B. \[4.2\times {{10}^{-3}}\,weber/{{m}^{2}}\] | |
| 9819. |
The capacity of a condenser in which a dielectric of dielectric constant 5 has been used, is \[C\]. If the dielectric is replaced by another with dielectric constant 20, the capacity will become [MP PMT 1996] |
| A. | \[\frac{C}{4}\] |
| B. | \[4C\] |
| C. | \[\frac{C}{2}\] |
| D. | \[2C\] |
| Answer» C. \[\frac{C}{2}\] | |
| 9820. |
Assertion : The resistance of super-conductor is zero. Reason : The super-conductors are used for the transmission of electric power. |
| 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. | |
| 9821. |
Assertion : Resonance is special case of forced vibration in which the natural frequency of vibration of the body is the same as the impressed frequency of external periodic force and the amplitude of forced vibration is maximum. Reason : The amplitude of forced vibrations of a body increases with an increase in the frequency of the externally impressed periodic force. [AIIMS 1994] |
| 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. | |
| 9822. |
A long copper tube of inner radius R carries a current i. The magnetic field B inside the tube is [MP PMT 1995] |
| A. | \[\frac{{{\mu }_{0}}i}{2\pi R}\] |
| B. | \[\frac{{{\mu }_{0}}i}{4\pi R}\] |
| C. | \[\frac{{{\mu }_{0}}i}{2R}\] |
| D. | Zero |
| Answer» E. | |
| 9823. |
The figure indicates the energy level diagram of an atom and the origin of six spectral lines in emission (e.g. line no. 5 arises from the transition from level B to A). The following spectral lines will also occur in the absorption spectrum [CBSE PMT 1995] |
| A. | 1, 4, 6 |
| B. | 4, 5, 6 |
| C. | 1, 2, 3 |
| D. | 1, 2, 3, 4, 5, 6 |
| Answer» D. 1, 2, 3, 4, 5, 6 | |
| 9824. |
The ratio of peak value and r.m.s value of an alternating current is [MP PMT 2002] |
| A. | 1 |
| B. | \[\frac{1}{2}\] |
| C. | \[\sqrt{2}\] |
| D. | \[1/\sqrt{2}\] |
| Answer» D. \[1/\sqrt{2}\] | |
| 9825. |
An electron initially at rest, is accelerated through a potential difference of 200 volt, so that it acquires a velocity \[8.4\times {{10}^{6}}m/s.\] The value of e/m of electron will be [DPMT 2003] |
| A. | \[2.76\times {{10}^{12}}C/kg\] |
| B. | \[1.76\times {{10}^{11}}C/kg\] |
| C. | \[0.76\times {{10}^{12}}C/kg\] |
| D. | None of these |
| Answer» C. \[0.76\times {{10}^{12}}C/kg\] | |
| 9826. |
An ideal gas is expanded adiabatically at an initial temperature of 300 K so that its volume is doubled. The final temperature of the hydrogen gas is \[(\gamma =1.40)\] [MP PMT 1995; DPMT 1999] |
| A. | 227.36 K |
| B. | 500.30 K |
| C. | 454.76 K |
| D. | \[-{{47}^{o}}C\] |
| Answer» B. 500.30 K | |
| 9827. |
If density of earth increased 4 times and its radius become half of what it is, our weight will [AMU (Engg.) 2001] |
| A. | Be four times its present value |
| B. | Be doubled |
| C. | Remain same |
| D. | Be halved |
| Answer» C. Remain same | |
| 9828. |
Temperature of water at the surface of lake is \[-{{20}^{o}}C.\]Then temperature of water just below the lower surface of ice layer is [RPET2000] |
| A. | \[-{{4}^{o}}C\] |
| B. | \[{{0}^{o}}C\] |
| C. | \[{{4}^{o}}C\] |
| D. | \[-{{20}^{o}}C\] |
| Answer» C. \[{{4}^{o}}C\] | |
| 9829. |
In general, metallic ropes are suspended on the carriers which take inflammable material. The reason is |
| A. | There speed is controlled |
| B. | To keep the centre of gravity of the carrier nearer to the earth |
| C. | To keep the body of the carrier in contact with the earth |
| D. | Nothing should be placed under the carrier |
| Answer» D. Nothing should be placed under the carrier | |
| 9830. |
A straight section PQ of a circuit lies along the X-axis from \[x=-\frac{a}{2}\] to \[x=\frac{a}{2}\] and carries a steady current i. The magnetic field due to the section PQ at a point X = + a will be [MP PMT 1987] |
| A. | Proportional to a |
| B. | Proportional to \[{{a}^{2}}\] |
| C. | Proportional to \[1/a\] |
| D. | Zero |
| Answer» E. | |
| 9831. |
Let \[\overrightarrow{C}=\overrightarrow{A}+\overrightarrow{B}\] then |
| A. | \[|\overrightarrow{C|}\] is always greater then \[|\overrightarrow{A}|\] |
| B. | It is possible to have \[|\overrightarrow{C}|\,<\,|\overrightarrow{A}|\] and \[|\overrightarrow{C}|\,<\,|\overrightarrow{B}|\] |
| C. | C is always equal to A + B |
| D. | C is never equal to A + B |
| Answer» C. C is always equal to A + B | |
| 9832. |
We can reduce eddy currents in the core of transformer [MP PET 1993] |
| A. | By increasing the number of turns in secondary coil |
| B. | By taking laminated core |
| C. | By making step-down transformer |
| D. | By using a weak ac at high potential |
| Answer» C. By making step-down transformer | |
| 9833. |
Spot the wrong statement: The acceleration due to gravity ?g? decreases if [MP PMT 1994] |
| A. | We go down from the surface of the earth towards its centre |
| B. | We go up from the surface of the earth |
| C. | We go from the equator towards the poles on the surface of the earth |
| D. | The rotational velocity of the earth is increased |
| Answer» D. The rotational velocity of the earth is increased | |
| 9834. |
Assertion : Electrons in the atom are held due to coulomb forces. Reason : The atom is stable only because the centripetal force due to Coulomb?s law is balanced by the centrifugal force. |
| 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. | |
| 9835. |
When a capillary is dipped in water, water rises to a heig ht \[h\]. If the length of the capillary is made less than\[h\], then |
| A. | The water will come out |
| B. | The water will not come out |
| C. | The water will not rise |
| D. | The water will rise but less than height of capillary |
| Answer» C. The water will not rise | |
| 9836. |
Electric field and magnetic field in Thomson mass spectrograph are applied [RPMT 1998] |
| A. | Simultaneously, perpendicular |
| B. | Perpendicular but not simultaneously |
| C. | Parallel but not simultaneously |
| D. | Parallel simultaneously |
| Answer» E. | |
| 9837. |
Due to capillary action, a liquid will rise in a tube, if the angle of contact is [DPMT 1984; AFMC 1988; BHU 2001] |
| A. | Acute |
| B. | Obtuse |
| C. | 90° |
| D. | Zero |
| Answer» B. Obtuse | |
| 9838. |
Assertion : To hear distinct beats, difference in frequencies of two sources should be less than 10. Reason : More the number of beats per sec more difficult to hear them. |
| 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. | |
| 9839. |
The heat is flowing through a rod of length 50 cm and area of cross-section \[5c{{m}^{2}}\]. Its ends are respectively at \[{{25}^{o}}C\] and \[{{125}^{o}}C\]. The coefficient of thermal conductivity of the material of the rod is 0.092 kcal/m×s×oC. The temperature gradient in the rod is [MP PET 2002] |
| A. | \[{{2}^{o}}C/cm\] |
| B. | \[{{2}^{o}}C/m\] |
| C. | \[{{20}^{o}}C/cm\] |
| D. | \[{{20}^{o}}C/m\] |
| Answer» B. \[{{2}^{o}}C/m\] | |
| 9840. |
Between the plates of a parallel plate condenser there is \[1mm\] thick paper of dielectric constant 4. It is charged at \[100\ volt\]. The electric field in \[volt/metre\]between the plates of the capacitor is [MP PMT 1994] |
| A. | 100 |
| B. | 100000 |
| C. | 25000 |
| D. | 4000000 |
| Answer» C. 25000 | |
| 9841. |
The wavelength of radiation emitted is \[{{\lambda }_{0}}\]when an electron jumps from the third to the second orbit of hydrogen atom. For the electron jump from the fourth to the second orbit of the hydrogen atom, the wavelength of radiation emitted will be [SCRA 1998; MP PET 2001; MH CET 2003] |
| A. | \[\frac{16}{25}{{\lambda }_{0}}\] |
| B. | \[\frac{20}{27}{{\lambda }_{0}}\] |
| C. | \[\frac{27}{20}{{\lambda }_{0}}\] |
| D. | \[\frac{25}{16}{{\lambda }_{0}}\] |
| Answer» C. \[\frac{27}{20}{{\lambda }_{0}}\] | |
| 9842. |
A stationary object at 4°C and weighing 3.5 kg falls from a height of 2000 m on a snow mountain at 0°C. If the temperature of the object just before hitting the snow is 0°C and the object comes to rest immediately \[(g=10\,m/{{s}^{2}})\] and (latent heat of ice\[=3.5\times {{10}^{5}}\,joule/\sec \]), then the object will melt [BHU 2001] |
| A. | 2 kg of ice |
| B. | 200 gm of ice |
| C. | 20 gm ice |
| D. | 2 gm of ice |
| Answer» C. 20 gm ice | |
| 9843. |
The power is transmitted from a power house on high voltage ac because [CPMT 1984, 85] |
| A. | Electric current travels faster at higher volts |
| B. | It is more economical due to less power wastage |
| C. | It is difficult to generate power at low voltage |
| D. | Chances of stealing transmission lines are minimized |
| Answer» C. It is difficult to generate power at low voltage | |
| 9844. |
Assertion : Reduction factor (K) of a tangent galvanometer helps in reducing deflection to current. Reason : Reduction factor increases with increase of current. |
| 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. | |
| 9845. |
Assertion : The position-time graph of a body moving uniformly is a straight line parallel to position-axis. Reason : The slope of position-time graph in a uniform motion gives the velocity of an object. |
| 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. | |
| 9846. |
Assertion : A compass needle when placed on the magnetic north pole of the earth rotates in vertical direction. Reason : The earth has only horizontal component of its magnetic field at the north poles. |
| 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. | |
| 9847. |
Assertion : Self-inductance is called the inertia of electricity. Reason : Self-inductance is the phenomenon, according to which an opposing induced e.m.f. is produced in a coil as a result of change in current or magnetic flux linked in the coil. |
| 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. | |
| 9848. |
Assertion : The fundamental frequency of an open organ pipe increases as the temperature is increased. Reason : As the temperature increases, the velocity of sound increases more rapidly than length of the pipe. |
| 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. | |
| 9849. |
At N.T.P. one mole of diatomic gas is compressed adiabatically to half of its volume\[\gamma =1.41\]. The work done on gas will be [RPET 1997] |
| A. | 1280 J |
| B. | 1610 J |
| C. | 1815 J |
| D. | 2025 J |
| Answer» D. 2025 J | |
| 9850. |
Work of electric motor is [RPMT 1997] |
| A. | To convert ac into dc |
| B. | To convert dc into ac |
| C. | Both (a) and (b) |
| D. | To convert ac into mechanical work |
| Answer» E. | |