MCQOPTIONS
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MCQOPTIONS
This section includes 39 Mcqs, each offering curated multiple-choice questions to sharpen your Physics knowledge and support exam preparation. Choose a topic below to get started.
| 1. |
A current carrying conductor is placed in a uniform magnetic field parallel to it. The magnetic force experienced by the conductor is |
| A. | F=1/B |
| B. | F=1/Bsin? |
| C. | F/0 |
| D. | F=1/Bcos? |
| Answer» D. F=1/Bcos? | |
| 2. |
A galvanometer basically is an instrument used to |
| A. | Detect current in a circuit |
| B. | Measure current flowing through a circuit |
| C. | Measure voltage across a circuit |
| D. | Measure potential difference between two points in a circuit |
| Answer» B. Measure current flowing through a circuit | |
| 3. |
A magnetic compass will be deflected if it is kept near a |
| A. | Charge in motion |
| B. | Charge at rest |
| C. | Both |
| D. | None |
| Answer» B. Charge at rest | |
| 4. |
A moving coil galvanometer of resistance 100? gives half scale deflection for a current of 20mA. What will be the potential difference across it? |
| A. | 4 volt |
| B. | 5 volt |
| C. | 2 volt |
| D. | 0.4 volt |
| Answer» D. 0.4 volt | |
| 5. |
A particle of mass m charge q and speed V enters a uniform magnetic radius r. The radius r of the circle is |
| A. | Independent mass m |
| B. | Directly proportional to m |
| C. | Directly proportional to q |
| D. | Directly proportional to B |
| Answer» C. Directly proportional to q | |
| 6. |
A sensitive galvanometer gives full-scale deflection with 100 mV. If the resistance of the galvanometer is 50? the maximum current that can flow through safely is |
| A. | 2.0 mA |
| B. | 20 mA |
| C. | 200 mA |
| D. | 0.2 mA |
| Answer» B. 20 mA | |
| 7. |
A wheat stone bridge is said to be balanced when |
| A. | Maximum current flows through the galvanometer branch |
| B. | Minimum current flows through the galvanometer branch |
| C. | Potential difference across galvanometer branch is maximum |
| D. | Potential difference across galvanometer branch is zero |
| Answer» E. | |
| 8. |
An ammeter measures the total current flowing through a circuit when it is connected |
| A. | In series with the circuit |
| B. | In parallel with circuit |
| C. | In series with any of the parallel resistances in the circuit |
| D. | In parallel with any of the series resistances in the circuit |
| Answer» B. In parallel with circuit | |
| 9. |
If the plane of the rectangular coil is parallel to the magnetic field (i.e radial magnetic field) the torque on the coil is |
| A. | ? = NIAB cos? |
| B. | ? = NIAB sin? |
| C. | ? = NIAB tan? |
| D. | ? = NIAB |
| Answer» E. | |
| 10. |
An electron enters a region where the electric field E is perpendicular to the magnetic field B. It will suffer no deflection if |
| A. | E = BeV |
| B. | B = eE/V |
| C. | E = BV |
| D. | E = BeV/2 |
| Answer» D. E = BeV/2 | |
| 11. |
Magnetic flux and flux density are related by |
| A. | Magnetic flux = flux density / area |
| B. | Magnetic flux = flux density x area |
| C. | Flux density = magnetic flux area |
| D. | Flux density = magnetic flux x area |
| Answer» C. Flux density = magnetic flux area | |
| 12. |
Minimum current required to produce a deflection of 1 mm on a scale at a distance of 1 meter is |
| A. | 0.1 A |
| B. | 1:00 AM |
| C. | Current sensitivity |
| D. | 1 m A |
| Answer» D. 1 m A | |
| 13. |
Magnetic force acting on a unit positive charge moving perpendicular to the magnetic field with a unit velocity is called |
| A. | Magnetic flux |
| B. | Magnetic field intensity |
| C. | Magnetic induction |
| D. | Self inductance |
| Answer» D. Self inductance | |
| 14. |
In a multi range ammeter as the range increases |
| A. | Shunt value decreases |
| B. | Shunt value increases |
| C. | Shunt value remains the same |
| D. | None of the above |
| Answer» B. Shunt value increases | |
| 15. |
SI unit of flux density is |
| A. | NA-1m-1 |
| B. | NAm-1 |
| C. | NmA-1 |
| D. | NmA-2 |
| Answer» B. NAm-1 | |
| 16. |
The charged particle enters the uniform magnetic field in such a way that its initial velocity is not perpendicular to the field the orbit will be |
| A. | A circle |
| B. | A spiral |
| C. | An ellipse |
| D. | Helix |
| Answer» E. | |
| 17. |
The deflection for 50 division of galvanometer is decreased to 25 divisions by shunt resistance of 12?. Galvanometer resistance is |
| A. | 18? |
| B. | 30? |
| C. | 24? |
| D. | 12? |
| Answer» E. | |
| 18. |
The magnetic field strength of solenoid is |
| A. | B = ??NI |
| B. | B = ??N/I |
| C. | B = ??nI |
| D. | Both (b) and (c) |
| Answer» E. | |
| 19. |
The effective way to increase the sensitivity of a moving coil galvanometer is to |
| A. | Use a very long and fine suspension |
| B. | Use a coil of very large area |
| C. | Use a coil with very large number of turns |
| D. | Use a very strong magnetic field |
| Answer» E. | |
| 20. |
Value of permeability of tree space in SI units is |
| A. | 4?x10-9 WbA-1m-1 |
| B. | 4?x10-7 WbA-1m-1 |
| C. | 4?x10-10 WbA-1m-1 |
| D. | 4?x10-8 WbA-1m-1 |
| Answer» C. 4?x10-10 WbA-1m-1 | |
| 21. |
The magnetic force experienced by a charge particle moving in a magnetic field will be minimum when it moves |
| A. | Perpendicular to the field |
| B. | Parallel to the field |
| C. | Inclined parallel to the field |
| D. | At an angle of 45? |
| Answer» C. Inclined parallel to the field | |
| 22. |
The relationship between Tesla and smaller unit Gauss of magnetic induction is given by |
| A. | 1T = 103 G |
| B. | 1T = 10-4 G |
| C. | 1T = 10-2 G |
| D. | 1T = 104 G |
| Answer» E. | |
| 23. |
The sensitivity of a galvanometer is given by |
| A. | C/BAN |
| B. | CAN/B |
| C. | BAN/C |
| D. | ABC/N |
| Answer» B. CAN/B | |
| 24. |
The standard vector symbol for flux density is |
| A. | M |
| B. | L |
| C. | H |
| D. | B |
| Answer» E. | |
| 25. |
Two parallel wires carrying currents in the opposite directions |
| A. | Repel each other |
| B. | Attract each other |
| C. | Have no effect upon each other |
| D. | They cancel out their individual magnetic fields |
| Answer» B. Attract each other | |
| 26. |
What is the value of the current in a wire of 10cm long at the right angle to a uniform magnetic field of 0.5 Weber/m2 when the force acting on the wire is 5N? |
| A. | 1A |
| B. | 10A |
| C. | 100A |
| D. | 1000A |
| Answer» D. 1000A | |
| 27. |
When a particle of charge q and mass m enters into a uniform magnetic field B moving with a velocity v perpendicular to the direction for the field it describes a circular path of radius |
| A. | R=qB/mV |
| B. | R=mV/qB |
| C. | R=qmV/B |
| D. | R=qmB/V |
| Answer» C. R=qmV/B | |
| 28. |
When a particle of charge q and mass m enters the uniform magnetic field B moving with velocity v perpendicular to the direction of the field the time required by a charged particle to make a complete revolution in a magnetic field is given by |
| A. | T= |
| B. | B |
| Answer» A. T= | |
| 29. |
When an electron moving with a uniform speed in a vacuum enters a magnetic field in a direction perpendicular to the field the subsequent path of the electron is |
| A. | A straight line parallel to the field |
| B. | A parabola in a plane perpendicular to the field |
| C. | A circle in a plane perpendicular to the field |
| D. | A straight line along its initial direction |
| Answer» D. A straight line along its initial direction | |
| 30. |
When the coil of the galvanometer is in equilibrium then the deflecting couple is |
| A. | Zero |
| B. | Equal to the restoring couple |
| C. | Greater than the restoring couple |
| D. | Smaller than the restoring couple |
| Answer» C. Greater than the restoring couple | |
| 31. |
Which one of the following is not an electromechanical instrument? |
| A. | Galvanometer |
| B. | Voltmeter |
| C. | Ammeter |
| D. | AC transformer and DC generator |
| Answer» E. | |
| 32. |
An instrument which can measure potential without drawing any current is |
| A. | Voltmeter |
| B. | Galvanometer |
| C. | Cathode ray oscilloscope (CRO) |
| D. | Ammeter |
| Answer» D. Ammeter | |
| 33. |
Which one of the following methods would be able to increase the sensitivity of a moving coil galvanometer ? |
| A. | Connect a shunt across the coil |
| B. | Use a coil of smaller cross sectional area |
| C. | Use a coil having less number of turns |
| D. | Use spiral springs whose force constant is small |
| Answer» E. | |
| 34. |
While measuring the unknown resistance the help of slide wire bridge a greatest accuracy can be achieved when |
| A. | A most sensitive galvanometer is used |
| B. | A steady voltage cell is used |
| C. | The balance point is close to the middle of the wire |
| D. | A high resistance box is used in one of its gap |
| Answer» D. A high resistance box is used in one of its gap | |
| 35. |
Coil of a galvanometer is suspended in a radial magnetic field so that the deflecting torque on the coil is always |
| A. | BINA cosa |
| B. | BINA sina |
| C. | BINA tana |
| D. | BINA |
| Answer» E. | |
| 36. |
Which one of the following material is most suitable for making core of an electromagnet? |
| A. | Air |
| B. | Steel |
| C. | Cu-Ni alloy |
| D. | Soft iron |
| Answer» E. | |
| 37. |
Galvanometer is a very sensitive device with |
| A. | Very low damping |
| B. | Very high damping |
| C. | No damping at all |
| D. | Radial field disintegration |
| Answer» B. Very high damping | |
| 38. |
Heating a magnet will |
| A. | Weaken it |
| B. | Strengthen it |
| C. | Reverse its polarity |
| D. | Demagnetize it completely |
| Answer» B. Strengthen it | |
| 39. |
If a current carrying solenoid is suspended freely it will |
| A. | Be rotating |
| B. | Come to rest in N-S direction |
| C. | Vibrating like galvanometer needle |
| D. | Comes to rest after rotation |
| Answer» C. Vibrating like galvanometer needle | |