InterviewSolution
Saved Bookmarks
InterviewSolution
This section includes InterviewSolutions, each offering curated multiple-choice questions to sharpen your knowledge and support exam preparation. Choose a topic below to get started.
| 401. |
Assertion: Reduction factor (K) of a tangent galvanometer helps in reduction 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 assertionC. f assertion is true but reason is false.D. If the assertion and r eason both are false |
|
Answer» Correct Answer - C |
|
| 402. |
To measure which of the following, is a tangent galvanometer usedA. ChargeB. AngleC. CurrentD. Magnetic intensity |
|
Answer» Correct Answer - C |
|
| 403. |
An iron ring having 500 turns of wire and mean diameter of 12 cm carries a current of 0.3 A. The relative permeability of iron is 600. What is the magnetic flux density in the core ? What is the magnetisation field intensity ? What part of the density is due to the electronic loop currents in the core ? |
|
Answer» Correct Answer - `0.3 Wbm^(-1) 397.9 A "turns" m^(-1), 0.2995 Wbm^(-2)` |
|
| 404. |
The radius of the coil of a Tangent galvanometer, which has 10 turns, is 0.1 m. The current required to produce a deflection of `60^(@) (B_(H)=4xx10^(-5)T)` isA. 0.125B. 1.1 AC. 2.1 AD. 1.5 A |
|
Answer» Correct Answer - B |
|
| 405. |
In a tangent galvanometer, when a current of `10mA` is passed, the deflection is `31^@`. By what percentage, the current has to be increased, so at to produce a deflection of `42^@`? |
|
Answer» Correct Answer - 0.5 |
|
| 406. |
Define the angle of dip. What happens to angle of dip as we move towards magnetic pole from magnetic equator? |
|
Answer» Angle made by the direction of resultant magnetic field with the horizontal at a place is inclination or angle of dip (ø) at the place. At the magnetic pole value of ø = 90° and it goes on decreasing when we move towards equator such that at equator value of (ø) = 0°. |
|
| 407. |
A magnet makes `10` oscilllations per minute at a place where the angle of dip is `45^(@)` and the total intensity is `0.4` gauss. The number of oscillations made per sec by the same magnet at another place where the angle of dip is `60^(@)` and the total intensity `0.5` gauss is approximately. |
|
Answer» Correct Answer - `9.45 "min"^(-1)` |
|
| 408. |
The magnetic moment of a bar magnet of geometric length 20 cm is `3.6xx10^(-6) Am^(2)` The magnetic length is 90% of its geometric length the pole strength isA. `2xx10^(-5)Am`B. `1.8 xx10^(-4) Am`C. `7.2 xx10^(-8) Am`D. `0.55 xx 10^(-4) Am` |
|
Answer» Correct Answer - A `2l=(5)/(6)xx"geo.length"` `(5)/(6)xx20=(100)/(6)cm` Now" "m`=(M)/(2l)=(3.6xx10^(-6)xx6)/(100xx10^(-2))` `19.6xx10^(-6)` `2xx10^(-5)Am` |
|
| 409. |
Two normal uniform magnetic field contain a magnetic needle making an angle `60^(@)` with F. Then the ratio of `F/H` isA. `1:2`B. `2:1`C. `sqrt(3):1`D. `1:sqrt(3)` |
|
Answer» Correct Answer - D |
|
| 410. |
A certain amount of current when flowing in a properly set tangent galvanoment, produces a deflection of `45^(@)`. If the current be reduced by a factor of `sqrt(3)`, the deflection wouldA. Decrease by `30°`B. Decrease by `15°`C. Increase by `15° `D. Increase by `30° ` |
|
Answer» Correct Answer - B |
|
| 411. |
Vibration magnetometer before use, should be setA. In magnetic meridianB. In geographical meridianC. Perpendicular to magnetic meridianD. In any position |
|
Answer» Correct Answer - A |
|
| 412. |
The coil of a tangent galvanometer is 11 cm in radius . How many turns of the wire should be wound on it if a current of `70 mu` A is to produce a deflection of `45^(@)` . Given `B_(H)=0.32` gauss. |
|
Answer» Correct Answer - 80 turns |
|
| 413. |
A current of 70 mA is passed through a tangent galvanometer of 50 turns having a coil connected to a battery of 6 V having internal resistance of `15Omega`. Find the galvanometer resistance. |
|
Answer» Correct Answer - 0.346 G |
|
| 414. |
Assertion: The tangent galvanometer can be made more sensitive by increasing the number of turns of its coil. Reason: Current through galvanometer is proportional to the number of turns of 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 assertionC. f assertion is true but reason is false.D. If the assertion and r eason both are false |
|
Answer» Correct Answer - B |
|
| 415. |
The time period of oscillation of a magnet in a vibration magnetometer is `1.5` seconds. The time period of oscillation of another of another magnet similar in size, shap and mass but having one-fourth magnetic moment than that of first magnet, oscillating at same place will beA. 0.75 secB. 1.5 secC. 3 secD. 6 sec |
|
Answer» Correct Answer - C |
|
| 416. |
A circular coil of radius `4 cm` and of `20` turns carries a current of `3` amperes. It is placed in a magnetic field of intensity of `0.5 weber//m^(2)`. The magnetic dipole moment of the coil is |
|
Answer» Correct Answer - `0.3 Am^(2) , -0.15 J` |
|
| 417. |
A flat circular coil of wire `8.4` in diameter has 28 turns of copper wire and carries a current of `3.6` A . If his coil is placed in a uniform magnetic field of `0.25` T . (a) what is the magnitude of the magnetic dipole moment and (b) how much energy is required to turn the coil from its stable equilibrium position through an angle of `180^(@)` ? |
|
Answer» Correct Answer - `0.558 Am^(2) , 0.279 J ` |
|
| 418. |
Why is it not possible to magnetize an iron bar beyond the saturation point ? |
| Answer» How is the strength of bar magnetic is related to the number of molecular magnets arranged in a orderly way ? Can we increase the strength of a bar magnet if maximum number of molecular magnets are arranged in an orderly way | |
| 419. |
Write the following steps in a sequential order to map the magnetic lines of force due to a current carrying straight conductor (A) Pass a wire through the centre of a rectangular shaped card board (B) Close the circuit. (C) Tap the card board (d) Sprinkle some iron filings on the card board (E) connect the wire to a battery and a key (F) Observe that the iron filings are arranged in concentric circular path with wire at the centre.A. AEDBCFB. AEDCBFC. ADECBFD. AEBDFC |
|
Answer» Correct Answer - A (i) Pass a wire thorugh the centre of a rectangular shaped card board . (ii) Connected thw eire to a battery and a key. (iii) Sprinkle some iron filings on the card board. (iv) Close the circuit. (v) Tap the card baord (Vi) Observe that the iron filing are arranged in concentric circular paths with wire at the centre. |
|
| 420. |
A substance placed near a strong magnet is attracted by it, substance can be _______.A. a magnetB. paramegnetic substanceC. ferromagnetic substanceD. All the above |
|
Answer» Correct Answer - D A magnet , paramagnetic substance and a ferromagnetic substance are attacted by magnets . |
|
| 421. |
In Which of the following devices is a permanent magnet not used ?A. Electric motorB. TelegraphC. GeneratorsD. Particle accelerators. |
|
Answer» Correct Answer - B Permanent magnets are used in electric motor, generator and particle accelerator. An electromagnet, which is a temporary magnet, is used in telegraph system. |
|
| 422. |
A student who checked some magnets in the school laboratory found out that their magnetic force is worn out. Give three reasons for that? |
|
Answer» Magnets lose their properties if they are:
These are the reasons for that their magnetic force is worn out. |
|
| 423. |
How does an electromagnetic train work? |
|
Answer» 1. Electromagnets are used in Electromagnetic train. 2. Electromagnets are magnetised only when current flows through them. 3. When the direction of current is changed, the poles of the electromagnets are also changed. 4. Like poles of the magnets which are attached at the bottom of the train and rai l track repel each other. 5. So, the train is lifted from the track up to a height of 10 cm. 6. We know that we can move any magnetic object with the force of attraction or repulsion properties of magnets. 7. This train also moves with the help of the magnets attached on the sides of track and the magnets fitted at the bottom sideway of the train. 8. By controlling the current, we can control the magnets and movement of the train. |
|
| 424. |
The above diagrame is the pattern of magnetic lines of force obtained when two magnets are placed with their magnetic axes coinciding. The magnetic poles x and y are______and ________respectively.A. north , southB. south , northC. north , northD. south , south |
| Answer» Correct Answer - D | |
| 425. |
Assertion: Magnetic lines of force never intersect. Reason: The direction of magnetic lines of force in a magnetic field is from north to south.A. Assertion and reason are correct and reason is the correct explanationB. Assertion is correct and reason is wrongC. Assertion and reason are correct but reason is not the correct explanation for the assertionD. Assertion and reason are wrong. |
| Answer» Correct Answer - C | |
| 426. |
When a magnet is broken into two parts,A. the bigger parts acts like the north pole.B. the smaller part acts like the north pole.C. both the parts will have both the poles.D. polarity of each part depends upon the material. |
|
Answer» Correct Answer - C As per the pair property of magnets, when a magnet is broken into two parts, both the parts behave like two magnets with two poles |
|
| 427. |
Pieces of iron or steel that acquires magnetic properties when it is rubbed with a magnet are called ………… |
|
Answer» Pieces of iron or steel that acquires magnetic properties when it is rubbed with a magnet are called artificial magnet. |
|
| 428. |
In the single touch method of magnetization , the north pole of a bar magnet is rubbed against a steel rod. Then the polarity of the end of the steel rod at which the magnet leavesA. is the south .B. is the north.C. depends upon the material.D. none of these |
| Answer» Correct Answer - A | |
| 429. |
In the electrical method of magnetization, the polarity of the end in which current flows in clockwise directionA. is the north poleB. is the sourth poleC. does not deped upon the direction of currrent flowD. cannot be determined |
|
Answer» Correct Answer - B In the electrical method of magnetization, if the current flows in clockwise direction, then south pole is formed. |
|
| 430. |
Assertion (A): Steel is attracted by a magnet Reason (R ): Steel is not a magnetic substanceA. Both `A` and `R` are true and `R` is the correct explanation of `A`.B. Both `A` and `R` are true and `R` is not correct explanation of `A`.C. `A` is true, But `R` is falseD. `A` is false, But `R` is true |
| Answer» Correct Answer - A | |
| 431. |
The substances which are slightly attracted by the magnet areA. DiamagneticB. PAramagneticC. FerromagneticD. Electomagnetic |
| Answer» Correct Answer - B | |
| 432. |
You are provided with iron filings and a bar magnet without labelling the poles of the magnet. Using this. 1. How will you identify the poles of the magnet? 2. Which part of the bar magnet attracts more iron filings? Why? |
|
Answer» 1. When we place the bar magnet in iron fillings large amount of iron fillings stick on the two ends of the bar magnet. These ends are poles of the magnet. 2. Poles will attract more iron filings. Because poles have high magnetic strength. |
|
| 433. |
Mariner’s compass is used to find the (a) speed (b) displacement (c) direction (d) motion |
|
Answer» (c) direction |
|
| 434. |
What is magnetic field? |
|
Answer» The space around a magnet in which its magnetic effect or influence is observed. |
|
| 435. |
A material produces a magnetic field which oppose the applied magnetic field, then it isA. DiamagneticB. ParamagneticC. ElectromagneticD. None of these |
| Answer» Correct Answer - B | |
| 436. |
The magnetic moment of the atoms of the paramagnetic substances is greater thanA. ZeroB. OneC. TwoD. Three |
| Answer» Correct Answer - A | |
| 437. |
The unit of magnetising field or magnetic intensity is ……… |
|
Answer» The unit of magnetising field or magnetic intensity is ampere metre 1. |
|
| 438. |
Define in terms of magnetising field. |
|
Answer» The magnetic field which is used to magnetize a sample or specimen is called the magnetising field. Magnetising field is a vector quantity and it denoted by \(\vec H\) and its unit is A m-1 . |
|
| 439. |
Match the following: 1. Compass – Maximum magnetic strength 2. Attraction – Like poles3. Repulsion – Opposite poles 4. Magnetic poles – Magnetic needle |
|
Answer» 1. Compass – Magnetic needle 2. Attraction – Opposite poles 3. Repulsion – Like poles 4. Magnetic poles – Maximum magnetic strength |
|
| 440. |
Fill in the blanks: 1. The magnetic strength is ……… at the poles. 2. A magnet has ………… magnetic poles. 3. Magnets are used in ……… for generating electricity. 4. ……… are used to lift heavy iron pieces. 5. A freely suspended bar magnet is always pointing along the ……… north-south direction. |
|
Answer» 1. maximum 2. two 3. dynamos 4. Electromagnets 5. geographic |
|
| 441. |
Match the following:1. Magnetite(a) Magnetic lines 2. A tiny pivoted magnet(b) Natural magnet3. Cobalt(c) Compass box4. Closed curves(d) Ferromagnetic material5. Bismuth(e) Diamagnetic material |
|
Answer» 1. Magnetite - (b) Natural magnet 2. A tiny pivoted magnet - (c) Compass box 3. Cobalt - (d) Ferromagnetic material 4. Closed curves - (a) Magnetic lines 5. Bismuth - (e) Diamagnetic material |
|
| 442. |
Choose the correct option: (a) If both assertion and reason are true and reason is the correct explanation of the assertion. (b) If both assertion and reason are true but reason is not the correct explanation of assertion. (c) If the assertion is true, but the reason is false. (d) If the assertion is false, but the reason is true.Assertion: The Earth’s magnetic field is due to iron present in its core. Reason: At a high temperature, a magnet loses its magnetic property or magnetism. |
|
Answer» (d) Assertion is false but the reason is true. Correct statement: The Earth’s magnetic field is due to the molten charged metallic fluid inside the Earth’s surface. |
|
| 443. |
Choose the correct option: (a) If both assertion and reason are true and reason is the correct explanation of the assertion. (b) If both assertion and reason are true but reason is not the correct explanation of assertion. (c) If the assertion is true, but the reason is false. (d) If the assertion is false, but the reason is true.Assertion: Iron filings are concentrated more at the magnetic poles. Reason: The magnets are so sharp. |
|
Answer» (b) Both assertion and reason are true but reason is not the correct explanation of assertion. |
|
| 444. |
Differentiate magnetic and non-magnetic substance. |
|
Answer» Magnetic substance: 1. It is attracted by magnets 2. Ex: Iron, Cobalt, Nickel Non-magnetic substance: 1. It is not attracted by magnets 2. Ex: Paper, Plastic, Glass |
|
| 445. |
Give the properties of magnets. |
|
Answer» 1. Like poles repel each other. 2. Unlike poles attract each other. |
|
| 446. |
Define – Poles of a magnet. |
|
Answer» The attractive force of the magnet is very large near the two ends. These two ends are called poles of a magnet |
|
| 447. |
Fill up the blanks: 1. The magnetic Ore is called as _____ 2. _____ magnets do not have a definite shape. 3. Man-made magnets are called _____ magnets. 4. A _____ is an instrument which is used to find directions. 5. _____ will also get affected by magnetic field. 6. For a _____ magnet a single piece of soft iron can be used as a magnetic keeper across the pole |
|
Answer» 1. magnetite 2. Natural 3. Artificial 4. compass 5. Cell phone 6. horse-shoe |
|
| 448. |
Electro magnetic trains can easily attain a speed of _______ km per hour.(a) 1200(b) 600(c) 100(d) 800 |
|
Answer» Correct answer is (b) 600 |
|
| 449. |
Magnets lose their property if they(a) heated(b) dropped from a height(c) hit with hammer(d) all of these |
|
Answer» (d) all of these |
|
| 450. |
Suggest one way to recognise the magnetic field of the earth. |
|
Answer» If we suspend a magnet such that it is free to swing, we see that it always rests in the north-south direction. The north pole of the magnet lies in the geographic north direction and the south pole of the magnet lies in the geographic south direction. So it aligns itself in N-S direction. |
|