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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.
| 4851. |
Three blocks of masses \[{{m}_{1}},\,{{m}_{2}}\] and \[{{m}_{3}}\] are connected by massless strings as shown on a frictionless table. They are pulled with a force \[{{T}_{3}}=40\,N\]. If \[{{m}_{1}}=10\,kg,\,{{m}_{2}}=6\,kg\] and \[{{m}_{3}}=4\,kg\], the tension \[{{T}_{2}}\] will be [MP PMT/PET 1998] |
| A. | 20 N |
| B. | 40 N |
| C. | 10 N |
| D. | 32 N |
| Answer» E. | |
| 4852. |
Three solids of masses \[{{m}_{1}},\,{{m}_{2}}\] and \[{{m}_{3}}\] are connected with weightless string in succession and are placed on a frictionless table. If the mass \[{{m}_{3}}\] is dragged with a force T, the tension in the string between \[{{m}_{2}}\] and \[{{m}_{3}}\] is [MP PET 1995] |
| A. | \[\frac{{{m}_{2}}}{{{m}_{1}}+{{m}_{2}}+{{m}_{3}}}T\] |
| B. | \[\frac{{{m}_{3}}}{{{m}_{1}}+{{m}_{2}}+{{m}_{3}}}T\] |
| C. | \[\frac{{{m}_{1}}+{{m}_{2}}}{{{m}_{1}}+{{m}_{2}}+{{m}_{3}}}T\] |
| D. | \[\frac{{{m}_{2}}+{{m}_{3}}}{{{m}_{1}}+{{m}_{2}}+{{m}_{3}}}T\] |
| Answer» D. \[\frac{{{m}_{2}}+{{m}_{3}}}{{{m}_{1}}+{{m}_{2}}+{{m}_{3}}}T\] | |
| 4853. |
Two bodies of mass 3 kg and 4 kg are suspended at the ends of massless string passing over a frictionless pulley. The acceleration of the system is \[(g=9.8\,m/{{s}^{2}})\] [MP PET 1994; CBSE PMT 2001] |
| A. | \[4.9\,m/{{s}^{2}}\] |
| B. | \[2.45\,m/{{s}^{2}}\] |
| C. | \[1.4\,m/{{s}^{2}}\] |
| D. | \[9.5\,m/{{s}^{2}}\] |
| Answer» D. \[9.5\,m/{{s}^{2}}\] | |
| 4854. |
Three blocks A, B and C weighing 1, 8 and 27 kg respectively are connected as shown in the figure with an inextensible string and are moving on a smooth surface. \[{{T}_{3}}\] is equal to 36 N. Then \[{{T}_{2}}\] is [EAMCET 1983] |
| A. | 18 N |
| B. | 9 N |
| C. | 3.375 N |
| D. | 1.25 N |
| Answer» C. 3.375 N | |
| 4855. |
Two masses of 4 kg and 5 kg are connected by a string passing through a frictionless pulley and are kept on a frictionless table as shown in the figure. The acceleration of 5 kg mass is |
| A. | \[49\,m/{{s}^{2}}\] |
| B. | \[5.44\,m/{{s}^{2}}\] |
| C. | \[19.5\,m/{{s}^{2}}\] |
| D. | \[2.72\,m/{{s}^{2}}\] |
| Answer» C. \[19.5\,m/{{s}^{2}}\] | |
| 4856. |
Three equal weights A, B and C of mass 2 kg each are hanging on a string passing over a fixed frictionless pulley as shown in the figure The tension in the string connecting weights B and C is [MP PET 1985; SCRA 1996] |
| A. | Zero |
| B. | 13 N |
| C. | 3.3 N |
| D. | 19.6 N |
| Answer» C. 3.3 N | |
| 4857. |
Two masses \[{{m}_{1}}\]and \[{{m}_{2}}\left( {{m}_{1}}>{{m}_{2}} \right)\]are connected by massless flexible and inextensible string passed over massless and frictionless pulley. The acceleration of centre of mass is [J&K CET 2005] |
| A. | \[{{\left( \frac{{{m}_{1}}-{{m}_{2}}}{{{m}_{1}}+{{m}_{2}}} \right)}^{2}}g\] |
| B. | \[\frac{{{m}_{1}}-{{m}_{2}}}{{{m}_{1}}+{{m}_{2}}}g\] |
| C. | \[\frac{{{m}_{1}}+{{m}_{2}}}{{{m}_{1}}-{{m}_{2}}}g\] |
| D. | Zero |
| Answer» B. \[\frac{{{m}_{1}}-{{m}_{2}}}{{{m}_{1}}+{{m}_{2}}}g\] | |
| 4858. |
Two masses M and M/2 are joint together by means of a light inextensible string passes over a frictionless pulley as shown in figure. When bigger mass is released the small one will ascend with an acceleration of [Kerala PET 2005] |
| A. | \[g/3\] |
| B. | \[3g/2\] |
| C. | \[g/2\] |
| D. | \[g\] |
| Answer» B. \[3g/2\] | |
| 4859. |
A block of mass 4 kg is suspended through two light spring balances A and B. Then A and B will read respectively [AIIMS 1995] |
| A. | 4 kg and zero kg |
| B. | Zero kg and 4 kg |
| C. | 4 kg and 4 kg |
| D. | 2 kg and 2 kg |
| Answer» D. 2 kg and 2 kg | |
| 4860. |
Two masses \[{{m}_{1}}=5\,kg\] and \[{{m}_{2}}=4.8\,kg\] tied to a string are hanging over a light frictionless pulley. What is the acceleration of the masses when they are free to move \[(g=9.8\,\,m/{{s}^{2}})\] [AIEEE 2004] |
| A. | \[0.2\,\,m/{{s}^{2}}\] |
| B. | \[9.8\,\,m/{{s}^{2}}\] |
| C. | \[5\,\,m/{{s}^{2}}\] |
| D. | \[4.8\,\,m/{{s}^{2}}\] |
| Answer» B. \[9.8\,\,m/{{s}^{2}}\] | |
| 4861. |
A rope of length L is pulled by a constant force F. What is the tension in the rope at a distance x from the end where the force is applied [MP PET 1996, 97, 2000] |
| A. | \[\frac{FL}{x}\] |
| B. | \[\frac{F(L-x)}{L}\] |
| C. | \[\frac{FL}{L-x}\] |
| D. | \[\frac{Fx}{L-x}\] |
| Answer» C. \[\frac{FL}{L-x}\] | |
| 4862. |
A light string passing over a smooth light pulley connects two blocks of masses \[{{m}_{1}}\] and \[{{m}_{2}}\] (vertically). If the acceleration of the system is g/8 then the ratio of the masses is [AIEEE 2002] |
| A. | 8 : 1 |
| B. | 9 : 7 |
| C. | 4 : 3 |
| D. | 5 : 3 |
| Answer» C. 4 : 3 | |
| 4863. |
One end of a massless rope, which passes over a massless and frictionless pulley P is tied to a hook C while the other end is free. Maximum tension that the rope can bear is 360 N. with what value of minimum safe acceleration (in \[m{{s}^{-2}})\] can a monkey of \[60\,kg\] move down on the rope [AIEEE 2002] |
| A. | 16 |
| B. | 6 |
| C. | 4 |
| D. | 8 |
| Answer» D. 8 | |
| 4864. |
A body of weight 2kg is suspended as shown in the figure. The tension \[{{T}_{1}}\] in the horizontal string (in kg wt) is [Kerala PMT 2002] |
| A. | \[2/\sqrt{3}\] |
| B. | \[\sqrt{3}/2\] |
| C. | \[2\sqrt{3}\] |
| D. | \[2\] |
| Answer» D. \[2\] | |
| 4865. |
Two masses \[{{m}_{1}}\] and \[{{m}_{2}}\] are attached to a string which passes over a frictionless smooth pulley. When \[{{m}_{1}}=10kg,\] \[{{m}_{2}}=6kg,\,\]the acceleration of masses is [Orissa JEE 2002] |
| A. | 20 \[m/{{s}^{2}}\] |
| B. | \[5m/{{s}^{2}}\] |
| C. | 2.5 \[m/{{s}^{2}}\] |
| D. | \[10m/{{s}^{2}}\] |
| Answer» D. \[10m/{{s}^{2}}\] | |
| 4866. |
Three blocks of masses 2 kg, 3 kg and 5 kg are connected to each other with light string and are then placed on a frictionless surface as shown in the figure. The system is pulled by a force \[F=10N,\] then tension \[{{T}_{1}}=\] [Orissa JEE 2002] |
| A. | 1N |
| B. | 5 N |
| C. | 8 N |
| D. | 10 N |
| Answer» D. 10 N | |
| 4867. |
Two masses of 5kg and 10kg are connected to a pulley as shown. What will be the acceleration of the system \[(g=\]acceleration due to gravity) [CBSE PMT 2000] |
| A. | \[g\] |
| B. | \[\frac{g}{2}\] |
| C. | \[\frac{g}{3}\] |
| D. | \[\frac{g}{4}\] |
| Answer» D. \[\frac{g}{4}\] | |
| 4868. |
A light string passes over a frictionless pulley. To one of its ends a mass of 6 kg is attached. To its other end a mass of 10 kg is attached. The tension in the thread will be [RPET 1996; JIPMER 2001, 02] |
| A. | 24.5 N |
| B. | 2.45 N |
| C. | 79 N |
| D. | 73.5 N |
| Answer» E. | |
| 4869. |
A 2 kg block is lying on a smooth table which is connected by a body of mass 1 kg by a string which passes through a pulley. The 1 kg mass is hanging vertically. The acceleration of block and tension in the string will be [RPMT 1997] |
| A. | \[3.27\,m/{{s}^{2}},\,6.54\,N\] |
| B. | \[4.38\,m/{{s}^{2}},\,6.54\,N\] |
| C. | \[3.27\,m/{{s}^{2}},\,9.86\,N\] |
| D. | \[4.38\,m/{{s}^{2}},\,9.86\,N\] |
| Answer» B. \[4.38\,m/{{s}^{2}},\,6.54\,N\] | |
| 4870. |
A block of mass \[{{m}_{1}}\] rests on a horizontal table. A string tied to the block is passed on a frictionless pulley fixed at the end of the table and to the other end of string is hung another block of mass \[{{m}_{2}}\]. The acceleration of the system is [EAMCET (Med.) 1995; DPMT 2000] |
| A. | \[\frac{{{m}_{2}}g}{({{m}_{1}}+{{m}_{2}})}\] |
| B. | \[\frac{{{m}_{1}}g}{({{m}_{1}}+{{m}_{2}})}\] |
| C. | g |
| D. | \[\frac{{{m}_{2}}g}{{{m}_{1}}}\] |
| Answer» B. \[\frac{{{m}_{1}}g}{({{m}_{1}}+{{m}_{2}})}\] | |
| 4871. |
A block of mass M is pulled along a horizontal frictionless surface by a rope of mass m. If a force P is applied at the free end of the rope, the force exerted by the rope on the block will be [CBSE PMT 1993; CPMT 1972, 75, 82; MP PMT 1996; AIEEE 2003] |
| A. | P |
| B. | \[\frac{Pm}{M+m}\] |
| C. | \[\frac{PM}{M+m}\] |
| D. | \[\frac{Pm}{M-m}\] |
| Answer» D. \[\frac{Pm}{M-m}\] | |
| 4872. |
Two ions having masses in the ratio 1 : 1 and charges 1 : 2 are projected into uniform magnetic field perpendicular to the field with speeds in the ratio 2 : 3. The ratio of the radii of circular paths along which the two particles move is [EAMCET 2003] |
| A. | 4 : 3 |
| B. | 2 : 3 |
| C. | 3 : 1 |
| D. | 1 : 4 |
| Answer» B. 2 : 3 | |
| 4873. |
A particle of charge \[-16\times {{10}^{-18}}\]coulomb moving with velocity \[10\,\,m{{s}^{-1}}\] along the x-axis enters a region where a magnetic field of induction B is along the y-axis, and an electric field of magnitude \[{{10}^{4}}\,\,V/m\]is along the negative z-axis. If the charged particle continues moving along the x-axis, the magnitude of B is [AIEEE 2003] |
| A. | \[{{10}^{-3}}Wb/{{m}^{2}}\] |
| B. | \[{{10}^{3}}Wb/{{m}^{2}}\] |
| C. | \[{{10}^{5}}Wb/{{m}^{2}}\] |
| D. | \[{{10}^{16}}Wb/{{m}^{2}}\] |
| Answer» C. \[{{10}^{5}}Wb/{{m}^{2}}\] | |
| 4874. |
A charged particle is released from rest in a region of steady uniform electric and magnetic fields which are parallel to each other the particle will move in a [IIT-JEE 1999; DPMT 2000; UPSEAT 2003] |
| A. | Straight line |
| B. | Circle |
| C. | Helix |
| D. | Cycloid |
| Answer» B. Circle | |
| 4875. |
An electron enters a region where electrostatic field is 20N/C and magnetic field is 5T. If electron passes undeflected through the region, then velocity of electron will be [DPMT 2002] |
| A. | \[0.25m{{s}^{-1}}\] |
| B. | \[2m{{s}^{-1}}\] |
| C. | \[4m{{s}^{-1}}\] |
| D. | \[8m{{s}^{-1}}\] |
| Answer» D. \[8m{{s}^{-1}}\] | |
| 4876. |
An electron (mass = 9´ 10?31kg. Charge = 1.6 ´ 10?19C) whose kinetic energy is 7.2 ´ 10?18 joule is moving in a circular orbit in a magnetic field of 9 ´ 10?5 weber/m2. The radius of the orbit is [MP PMT 2002] |
| A. | 1.25 cm |
| B. | 2.5 cm |
| C. | 12.5 cm |
| D. | 25.0 cm |
| Answer» E. | |
| 4877. |
Mixed \[H{{e}^{+}}\] and \[{{O}^{2+}}\]ions (mass of \[H{{e}^{+}}=4\,\,amu\] and that of \[{{O}^{2+}}=16\,\,amu)\] beam passes a region of constant perpendicular magnetic field. If kinetic energy of all the ions is same then [Orissa JEE 2002] |
| A. | \[H{{e}^{+}}\] ions will be deflected more than those of \[{{O}^{2+}}\] |
| B. | \[H{{e}^{+}}\]ions will be deflected less than those of \[{{O}^{2+}}\] |
| C. | All the ions will be deflected equally |
| D. | No ions will be deflected |
| Answer» D. No ions will be deflected | |
| 4878. |
At a specific instant emission of radioactive compound is deflected in a magnetic field. The compound can emit (i) Electrons (ii) Protons (iii) \[H{{e}^{2+}}\] (iv) Neutrons The emission at the instant can be [AIEEE 2002] |
| A. | i, ii, iii |
| B. | i, ii, iii, iv |
| C. | iv |
| D. | ii, iii |
| Answer» B. i, ii, iii, iv | |
| 4879. |
If cathode rays are projected at right angles to a magnetic field, their trajectory is [JIPMER 2002] |
| A. | Ellipse |
| B. | Circle |
| C. | Parabola |
| D. | None of these |
| Answer» C. Parabola | |
| 4880. |
If the direction of the initial velocity of the charged particle is perpendicular to the magnetic field, then the orbit will be or The path executed by a charged particle whose motion is perpendicular to magnetic field is [MP PMT 1993; CPMT 1996] |
| A. | A straight line |
| B. | An ellipse |
| C. | A circle |
| D. | A helix |
| Answer» D. A helix | |
| 4881. |
When a charged particle enters a uniform magnetic field its kinetic energy [MP PMT 2001; MP PET 2002] |
| A. | Remains constant |
| B. | Increases |
| C. | Decreases |
| D. | Becomes zero |
| Answer» B. Increases | |
| 4882. |
Motion of a moving electron is not affected by [AMU (Engg.) 2001] |
| A. | An electric field applied in the direction of motion |
| B. | Magnetic field applied in the direction of motion |
| C. | Electric field applied perpendicular to the direction of motion |
| D. | Magnetic field applied perpendicular to the direction of motion |
| Answer» C. Electric field applied perpendicular to the direction of motion | |
| 4883. |
An \[\alpha \] particle and a proton travel with same velocity in a magnetic field perpendicular to the direction of their velocities, find the ratio of the radii of their circular path [AIIMS 2004; DCE 2001, 03; Kerala PMT 2005] |
| A. | 4 : 1 |
| B. | 1 : 4 |
| C. | 2 : 1 |
| D. | 1 : 2 |
| Answer» D. 1 : 2 | |
| 4884. |
A particle of mass 0.6 g and having charge of 25 nC is moving horizontally with a uniform velocity \[\text{1}\text{.2}\times \text{1}{{\text{0}}^{\text{4}}}m{{s}^{-1}}\] in a uniform magnetic field, then the value of the magnetic induction is \[(g=10\,m{{s}^{-2}})\] [EAMCET 2001] |
| A. | Zero |
| B. | 10 T |
| C. | 20 T |
| D. | 200 T |
| Answer» D. 200 T | |
| 4885. |
A proton and an alpha particle are separately projected in a region where a uniform magnetic field exists. Their initial velocities are perpendicular to direction of magnetic field. If both the particles move around magnetic field in circles of equal radii, the ratio of momentum of proton to alpha particle \[\left( \frac{{{P}_{p}}}{{{P}_{\alpha }}} \right)\]is [MP PET 2001] |
| A. | 1 |
| B. | \[\frac{1}{2}\] |
| C. | 2 |
| D. | \[\frac{1}{4}\] |
| Answer» C. 2 | |
| 4886. |
Cyclotron is used to accelerate [AIIMS 2001; BCECE 2004] |
| A. | Electrons |
| B. | Neutrons |
| C. | Positive ions |
| D. | Negative ions |
| Answer» D. Negative ions | |
| 4887. |
The radius of circular path of an electron when subjected to a perpendicular magnetic field is [Pb. PMT 1999; DCE 2000; MH CET (Med.) 2000] |
| A. | \[\frac{mv}{Be}\] |
| B. | \[\frac{me}{Be}\] |
| C. | \[\frac{mE}{Be}\] |
| D. | \[\frac{Be}{mv}\] |
| Answer» B. \[\frac{me}{Be}\] | |
| 4888. |
A homogeneous electric field E and a uniform magnetic field \[\overset{\to }{\mathop{B}}\,\] are pointing in the same direction. A proton is projected with its velocity parallel to \[\overset{\to }{\mathop{E}}\,\]. It will [Roorkee 2000] |
| A. | Go on moving in the same direction with increasing velocity |
| B. | Go on moving in the same direction with constant velocity |
| C. | Turn to its right |
| D. | Turn to its left |
| Answer» B. Go on moving in the same direction with constant velocity | |
| 4889. |
An electron (charge q coulomb) enters a magnetic field of H \[weber/{{m}^{2}}\] with a velocity of \[v\,m/s\] in the same direction as that of the field the force on the electron is [MP PET 2000] |
| A. | Hqv Newton?s in the direction of the magnetic field |
| B. | Hqv dynes in the direction of the magnetic field |
| C. | Hqv Newton?s at right angles to the direction of the magnetic field |
| D. | Zero |
| Answer» E. | |
| 4890. |
An electron (mass = 9.0×\[{{10}^{-31}}\]kg and charge =\[1.6\times {{10}^{-19}}\]coulomb) is moving in a circular orbit in a magnetic field of \[1.0\times {{10}^{-4}}\,weber/{{m}^{2}}.\] Its period of revolution is [MP PET 2000; Pb PET 2003] |
| A. | \[3.5\times {{10}^{-7}}\]sec |
| B. | \[7.0\times {{10}^{-7}}\]sec |
| C. | \[1.05\times {{10}^{-6}}\]sec |
| D. | \[2.1\times {{10}^{-6}}\]sec |
| Answer» B. \[7.0\times {{10}^{-7}}\]sec | |
| 4891. |
A charged particle moving in a magnetic field experiences a resultant force [MP PMT 1994] |
| A. | In the direction of field |
| B. | In the direction opposite to that field |
| C. | In the direction perpendicular to both the field and its velocity |
| D. | None of the above |
| Answer» D. None of the above | |
| 4892. |
An electron moving towards the east enters a magnetic field directed towards the north. The force on the electron will be directed [MP PET 2000] |
| A. | Vertically upward |
| B. | Vertically downward |
| C. | Towards the west |
| D. | Towards the south |
| Answer» C. Towards the west | |
| 4893. |
A particle of mass m and charge q enters a magnetic field B perpendicularly with a velocity v, The radius of the circular path described by it will be [MP PMT 2000] |
| A. | \[Bq/mv\] |
| B. | \[mq/Bv\] |
| C. | \[mB/qv\] |
| D. | \[mv/Bq\] |
| Answer» E. | |
| 4894. |
If an electron enters a magnetic field with its velocity pointing in the same direction as the magnetic field, then [MP PMT 2000] |
| A. | The electron will turn to its right |
| B. | The electron will turn to its left |
| C. | The velocity of the electron will increase |
| D. | The velocity of the electron will remain unchanged |
| Answer» E. | |
| 4895. |
A charge of 1C is moving in a magnetic field of 0.5Tesla with a velocity of 10m/sec Perpendicular to the field. Force experienced is [RPMT 2000] |
| A. | 5 N |
| B. | 10 N |
| C. | 0.5 N |
| D. | 0 N |
| Answer» B. 10 N | |
| 4896. |
An electron of mass m and charge q is travelling with a speed v along a circular path of radius r at right angles to a uniform of magnetic field B. If speed of the electron is doubled and the magnetic field is halved, then resulting path would have a radius of [Kerala PMT 2004; KCET 2000, 05] |
| A. | \[\frac{r}{4}\] |
| B. | \[\frac{r}{2}\] |
| C. | \[2r\] |
| D. | \[4r\] |
| Answer» E. | |
| 4897. |
An electron is travelling in east direction and a magnetic field is applied in upward direction then electron will deflect in [RPET 2000] |
| A. | South |
| B. | North |
| C. | West |
| D. | East |
| Answer» C. West | |
| 4898. |
A charge q is moving in a magnetic field then the magnetic force does not depend upon [RPET 2000] |
| A. | Charge |
| B. | Mass |
| C. | Velocity |
| D. | Magnetic field |
| Answer» C. Velocity | |
| 4899. |
A proton moving with a velocity, \[2.5\times {{10}^{7}}m/s\], enters a magnetic field of intensity 2.5T making an angle \[{{30}^{o}}\] with the magnetic field. The force on the proton is [AFMC 2000; CBSE PMT 2000] |
| A. | \[3\times {{10}^{-12}}N\] |
| B. | \[5\times {{10}^{-12}}N\] |
| C. | \[6\times {{10}^{-12}}\]N |
| D. | \[9\times {{10}^{-12}}N\] |
| Answer» C. \[6\times {{10}^{-12}}\]N | |
| 4900. |
A proton (mass m and charge +e) and an \[\alpha -\]particle (mass 4m and charge +2e) are projected with the same kinetic energy at right angles to the uniform magnetic field. Which one of the following statements will be true [NCERT 1983] |
| A. | The \[\alpha -\]particle will be bent in a circular path with a small radius that for the proton |
| B. | The radius of the path of the \[\alpha -\]particle will be greater than that of the proton |
| C. | The \[\alpha -\]particle and the proton will be bent in a circular path with the same radius |
| D. | The \[\alpha -\]particle and the proton will go through the field in a straight line |
| Answer» D. The \[\alpha -\]particle and the proton will go through the field in a straight line | |