datavorous/entrance-exam-dataset huggingface dataset:
What is incorrect about the resting state of neuron?

Options:
A High concentration of K+ and negatively charged proteins and low concentration of Na+ in axoplasm.
B Axonal membrane is nearly impermeable to Na+ .
C Axonal membrane is more permeable to K+ .
D Outer surface of axon is negatively charged.

The correct answer is:
Outer surface of axon is negatively charged.

Solution:
During resting state of neuron, axonal membrane is
A. More permeable to K+.
B. Nearly Impermeable to Na+.
C. Impermeable to negatively charged proteins present in the axoplasm.
- The high concentration of K+ and negatively charged proteins and low concentration of Na+ in axoplasm.
- In contrast, the fluid outside the axon contains a low concentration of K+, a high concentration of Na+ and thus form a concentration gradient.
- These ionic gradients across the resting membrane are maintained by the NaâK pump which actively transports 3Na+ outwards for 2K+ into the cell.
- The outer surface of the axonal membrane is positively charged. The inner surface of axonal membrane is negatively charged.
- The axonal membrane is polarised and the potential difference is known as resting potential.

Topic: Biology, Neural Control and Coordination, NEET
What is Inspiratory Capacity (IC)?

Options:
A Total volume of air a person can expire after a normal inspiration
B Total volume of air a person can inspire after a normal expiration
C Volume of air remaining in the lungs after a normal expiration
D Volume of air that will remain in the lungs after a forceful expiration

The correct answer is:
Total volume of air a person can inspire after a normal expiration

Solution:
Inspiratory Capacity (IC) is the total volume of air a person can inspire after a normal expiration, which includes tidal volume and inspiratory reserve volume (TV+IRV).

Topic: Biology, Breathing and Exchange of Gases, NEET
What is it that forms the basis of DNA fingerprinting?

Options:
A The relative proportions of purines and pyrimidines in DNA
B The relative difference in the DNA occurrence in blood, skin and saliva
C The relative amount of DNA in the ridges and grooves of the fingerprints
D Satellite DNA occurring as highly repeated short DNA segments

The correct answer is:
Satellite DNA occurring as highly repeated short DNA segments

Solution:
DNA fingerprint is individual specific DNA identification which is made possible by the finding that no two people are likely to have the same number of copies of repetitive DNA sequences of regions. The chromosomes of every human cells contain short, highly repeated DNA sequence (15 nucleotide) called minisatellite scatterd throughout.

Topic: Biology, Molecular Basis of Inheritance, NEET, NEET 2012 (Mains)
What is IUPAC name of following compound?

Options:
A 3-Carboxy-4-methyl benzoic acid
B 5-Carboxy-4-methyl benzoic acid
C 3-Formyl-6-methyl benzoic acid
D 5-Formyl-2-methyl benzoic acid

The correct answer is:
5-Formyl-2-methyl benzoic acid

Solution:
5-formyl-2-methyl benzoic acid

Topic: Chemistry, General Organic Chemistry, JEE Main
What is left in the solution during electrolytic refining?

Options:
A More basic metals
B Less basic metals
C Metal salts
D Impurities

The correct answer is:
More basic metals

Solution:
The more basic metal remains dissolved in the electrolytic bath during this process.

Topic: Chemistry, General Principles and Processes of Isolation of Metals, NEET
What is meant by emasculation? When and why does a plant breeder employ this technique?

Options:

None

Solution:
Emasculation is the removal of stamens mainly the anthers from the flower buds before their dehiscence. This is mainly done to avoid self-pollination. Emasculation is one of the measures in the artificial hybridization. Plant breeders employed this technique to prevent the pollination within same flower or to pollinate stigmas with pollens of desired variety.

Topic: Biology, Sexual Reproduction in Flowering Plants
What is meant by hybridisation of atomic orbitals? Describe the shapes of \(s p, s p^2\) and \(s p^3\) hybrid orbitals?

Options:

None

Solution:
Hybridization is defined as the mixing of the atomic orbitals belonging to the same atom but having slightly different energies so that a redistribution of energy takes place between them resulting in the formation of new orbitals of equal energies and identical shapes. The new orbitals thus formed are known as hybrid orbitals..
\(s p\) - hybridization :- when one \(s\) and one p orbital belonging to the same main shell of an atom mix together to form two new equivalent orbitals type of hybridisation is called \(s p\) hybridisation.
\(\boldsymbol{s p} \mathbf{p}^2\)-hybridization :- when one \(s\) and two \(p\) orbitals of the same shell of an atom mix to form three new equivalent orbitals, the type of hybridization is called \(s p^2\) hybrid orbitals.
\(s p^3\)-hybridization :- when one \(s\) and three \(p\) orbitals of the same shell of an atom mix to form four new equivalent orbitals, the type of hybridization is called \(s p^3\) hybrid orbitals.

Topic: Chemistry, Chemical Bonding and Molecular Structure
What is meant by modification of root? What type of modification of root is found in the:
(a) Banyan tree
(b) Turnip
(c) Mangrove trees.

Options:

None

Solution:
When roots are modified to carry out some additional functions like storage of food, additional mechanical support, other than absorption of water, minerals and main support to plant then, they represent modification of roots.
(a) In banyan tree, adventitious roots are modified into hanging supporting roots for giant banyan tree. These roots develop from branches and provides additional support to reach down the ground. Hence this modification is prop root.
(b) Tap roots of turnip get swollen and modified for storage of food. Such roots are called napiform roots.
(c) In mangrove tree, roots come out from ground and grow vertically. Such roots are called pneumatophores or respiratory roots. They help to get oxygen for respiration, to get modified into pneumatic structures. Mangrove trees generally grow in marshy area.

Topic: Biology, Morphology of Flowering Plants
What is meant by the term osmoregulation?

Options:

None

Solution:
Osmoregulation. It is the maintenance of a fixed osmotic concentration inside the body cells and the extracellular fluids by controlling the amount of water and salts.

Topic: Biology, Excretory Products and their Elimination
What is monomer for Orlon polymer

Options:
A Styrene
B Tetrafluoro ethylene
C Vinyl chloride
D Acrylonitrile

The correct answer is:
Acrylonitrile

Solution:
Acrylonitrile is a hard, horny and high melting material. It is used in the manufacture of oron and Acrilan fibres which are used for making clothes, carpets and blankets.

Topic: Chemistry, Polymers, JEE Main
What is necessary for the introduced DNA to be maintained in the host and transferred to its progeny?

Options:
A Identification of DNA with desirable genes
B Introduction of the identified DNA into the host
C Maintenance of introduced DNA in the host and transfer to its progeny
D Cloning of the desired genes in E. coli

The correct answer is:
Maintenance of introduced DNA in the host and transfer to its progeny

Solution:
For the introduced DNA to be maintained in the host and transferred to its progeny, the maintenance of introduced DNA in the host and transfer to its progeny is necessary.

Topic: Biology, Biotechnology - Principles and Processes, NEET
What is not true for genetic code?

Options:
A It is unambiguous
B A codon in mRNA is read in a noncontiguous fashion
C It is nearly universal
D It is degenerate

The correct answer is:
A codon in mRNA is read in a noncontiguous fashion

Solution:
No Solution Available

Topic: Biology, Molecular Basis of Inheritance, NEET, NEET 2009 (Mains)
What is obtained when chlorine is passed in boiling toluene and product is hydrolysed?

Options:
A o-cresol
B p-cresol
C 2,4-dihydroxytoluene
D Benzyl alcohol

The correct answer is:
Benzyl alcohol

Solution:
When chlorine is passed in boiling toluene, substitution in side-chain takes place and benzyl chloride is obtained which on hydrolysis give benzyl alcohol.

Topic: Chemistry, Hydrocarbons, JEE Main
What is obtained when nitrobenzene is treated sequentially with (i) $\mathrm{NH}_4 \mathrm{Cl} / \mathrm{Zn}$ dust and (ii) $\mathrm{H}_2 \mathrm{SO}_4 / \mathrm{Na}_2 \mathrm{Cr}_2 \mathrm{O}_7$ ?

Options:
A meta-chloronitrobenzene
B para-chloronitrobenzene
C nitrosobenzene
D benzene

The correct answer is:
nitrosobenzene

Solution:
Hints:

Topic: Chemistry, Hydrocarbons, JEE Main
What is one of the main reasons for the increased use of DDT after World War II?

Options:
A Its low cost
B Its effectiveness against malaria-carrying mosquitoes
C Its pleasant smell
D Its rapid degradation in the environment

The correct answer is:
Its effectiveness against malaria-carrying mosquitoes

Solution:
The use of DDT increased enormously after World War II primarily because of its effectiveness against the mosquito that spreads malaria and lice that carry typhus.

Topic: Chemistry, Haloalkanes and Haloarenes, NEET
What is pancreas? Mention the major secretions of pancreas that are helpful in digestion.

Options:

None

Solution:
The pancreas is both exocrine and as well as gland endocrine situated between the limbs of ' $U$ ' shaped duodenum.
Internal structure of pancreas consist of two parts, i.e., the exocrine and endocrine part.
(i) Exocrine part consists of rounded lobules called acini, that secretes alkaline pancreatic juice of $\mathrm{pH} 8.4$ and is mainly involved in the digestion of starch, proteins, fats and nucleic acids.
(ii) Endocrine part secretes hormones like, insulin and glucagon that regulate glucose metabolism.

Topic: Biology, Digestion and Absorption
What is produced when \(\mathrm{CH}_3 \mathrm{CONH}_2\) reacts with NaOBr?

Options:
A $\mathrm{CH}_3 \mathrm{Br}$
B $\mathrm{CH}_4$
C $\mathrm{CH}_3 \mathrm{COBr}$
D $\mathrm{CH}_3 \mathrm{NH}_2$

The correct answer is:
$\mathrm{CH}_3 \mathrm{NH}_2$

Solution:

Topic: Chemistry, Amines, JEE Main
What is Red Data Book?

Options:

None

Solution:
Red Data Book is a compilation of data or records of species on the verge of extinction or species that are endangered. That as he book is maintained by IUCN.

Topic: Biology, Biodiversity and its Conservation
What is reflection property of an ellipse?

Options:
A When a ray leaves one of the foci and meets a point on that ellipse, it will reflect off of the ellipse and does not pass through the other focus.
B When a ray leaves one of the foci and meets a point on that ellipse, it will reflect off of the ellipse and pass through the pole.
C When a ray leaves one of the foci and meets a point on that ellipse, it will reflect off of the ellipse and pass through the other focus.
D None of the above

The correct answer is:
When a ray leaves one of the foci and meets a point on that ellipse, it will reflect off of the ellipse and pass through the other focus.

Solution:
Correct option is $\mathrm{C}$. When a ray leaves one of the foci and meets a point on that ellipse, it will reflect off of the ellipse and pass through the other focus.

Topic: Mathematics, Ellipse, JEE Main
What is Residual Volume (RV)?

Options:
A The volume of air a person can inspire by a normal inspiration
B The volume of air a person can expire by a normal expiration
C The volume of air remaining in the lungs even after a forcible expiration
D The volume of air a person can inspire by a forceful inspiration

The correct answer is:
The volume of air remaining in the lungs even after a forcible expiration

Solution:
Residual Volume (RV) is the volume of air remaining in the lungs even after a forcible expiration, which averages 1100 mL to 1200 mL.

Topic: Biology, Breathing and Exchange of Gases, NEET
What is $\left(\frac{\sec 18^{\circ}}{\sec 144^{\circ}}+\frac{\operatorname{cosec} 18^{\circ}}{\operatorname{cosec} 144^{\circ}}\right)$ equal to?

Options:
A $\sec 18^{\circ}$
B $\operatorname{cosec} 18^{\circ}$
C $-\sec 18^{\circ}$
D $-\operatorname{cosec} 18^{\circ}$

The correct answer is:
$\sec 18^{\circ}$

Solution:
$\begin{aligned} \text { Consider }\left(\frac{\sec 18^{\circ}}{\sec 144^{\circ}}+\frac{\cos e c 18^{\circ}}{\cos e c 144^{\circ}}\right) \\=& \frac{\sec 18^{\circ}}{\sec \left(180^{\circ}-36^{\circ}\right)}+\frac{\cos e c 18^{\circ}}{\cos e c\left(180^{\circ}-36^{\circ}\right)} \\=&-\frac{\sec 18^{\circ}}{\sec 36^{\circ}}+\frac{\cos e c 18^{\circ}}{\cos e c 36^{\circ}}(\because \sin , \operatorname{cosec} \operatorname{are}+\mathrm{ve}\\ & \left.\text { in } 2^{\text {nd }} \text { quadrant and sec is }-\text { ve in } 2^{\text {nd }} \text { quadrant }\right) \\=& \frac{\sin 36^{\circ}}{\sin 18^{\circ}}-\frac{\cos 36^{\circ}}{\cos 18^{\circ}}=\frac{\sin 36^{\circ} \cos 18^{\circ}-\cos 36^{\circ} \sin 18^{\circ}}{\sin 18^{\circ} \cos 18^{\circ}} \\=& \frac{\sin \left(36^{\circ}-18^{\circ}\right)}{\sin 18^{\circ} \cos 18^{\circ}}=\frac{\sin 18^{\circ}}{\sin 18^{\circ} \cos 18^{\circ}}=\sec 18^{\circ} \\ &\left(\because \frac{1}{\cos x}=\sec x\right) \end{aligned}$

Topic: Mathematics, Trigonometric Equations, JEE Main
What is Slash and burn agriculture?

Options:
A The process of planting trees in a deforested area
B The cutting down of trees for timber, firewood, and cattle ranching
C The cutting down of trees in a forest and burning the plant remains for farming or cattle grazing.
D The preservation of forests

The correct answer is:
The cutting down of trees in a forest and burning the plant remains for farming or cattle grazing.

Solution:
Slash and burn agriculture, also known as Jhum cultivation, involves cutting down trees in a forest and burning the plant remains for farming or cattle grazing.

Topic: Biology, Environmental Issues, NEET
What is so special about tropics that might account for their greater biological diversity?

a. Unlike temperate regions subjected to frequent glaciations in the past, tropical latitudes have remained relatively undisturbed for millions of years and thus, had a long evolutionary time for species diversification.

b. Temperate environments, unlike tropical ones, are less seasonal, relatively more constant and predictable. Such constant environments promote niche specialization and lead to greater species diversity.

c. There is more solar energy available in the tropics, which contributes to higher productivity; this in turn might contribute indirectly to greater diversity.

Options:
A a only
B b and c
C a and c
D a, b and c

The correct answer is:
a and c

Solution:
The region near the middle of the Earth between the Tropic of Cancer and Tropic of Capricorn is considered as the tropic region. This region receives the most amount of solar energy which leads to better productivity and higher species diversity. Also, the seasonal variations in such regions are low and the environment mainly remains the same supporting high species richness and promoting niche specialization. Species-area relationships show a rectangular hyperbolic function.
Temperate regions include the subtropics and polar circles. These regions faced glaciation during the ice age which was not observed in the tropic regions.

Topic: Biology, Organisms and Populations, NEET
What is sulphur a main constituent of?

Options:
A Cysteine and methionine
B Thiamine and biotin
C Coenzyme A and ferredoxin
D All of the above

The correct answer is:
All of the above

Solution:
Sulphur is present in two amino acids (cysteine and methionine) and is the main constituent of several coenzymes, vitamins (thiamine, biotin, Coenzyme A) and ferredoxin.

Topic: Biology, Mineral Nutrition, NEET
What is the absolute pressure at a depth of 1000 m in an ocean, where the interior of a submarine with a window area of 20 cm × 20 cm is maintained at sea-level atmospheric pressure? (The density of seawater is 1.03 × 10³ kg/m³, g = 10 m/s².)

Options:
A 104 atm
B 109 atm
C 100 atm
D 102 atm

The correct answer is:
104 atm

Solution:
Correct Option is : (A)
104 atm

Topic: Chemistry, Mechanical Properties of Fluids, NEET
What is the accumulation of diatom cell wall deposits over billions of years referred to as?

Options:
A Diatomaceous earth
B Diatom sediment
C Diatom fossil
D Diatom layer

The correct answer is:
Diatomaceous earth

Solution:
The accumulation of diatom cell wall deposits over billions of years is referred to as "diatomaceous earth." Diatomaceous earth is a sedimentary rock composed mostly of the fossilized remains of diatoms, small aquatic algae.

Topic: Biology, Biological Classification, NEET
What is the activation energy for the decomposition of N2O5 as,

N2O5â2NO2+12O2

If the values of rate constant are 3.45Ã10-5 at 27â and =6.9Ã10-3 at 67â?

Options:
A 112.3 kJâ mol â1
B 200.5 kJ  mol −1
C 149.5 kJ  mol −1
D 11.25 kJ  mol −1

The correct answer is:
112.3 kJâ mol â1

Solution:
To be solved with the help of formula,
log k 2 k 1 = E a 2.303 R T 2 â T 1 T 1 T 2
T 1 =273+27=300 K
T 2 =273+67=340 K
log 6.9Ã 10 â3 3.45Ã 10 â5 = E a 2.303Ã8.31 340â300 340Ã300
logâ200= E a 19.1379 Ã 40 102000
2.3010=Ea19.14Ã410200
E a = 19.14Ã10200Ã2.3010 4
=â112304.907 Jâ mol â1 â=â112.3 kJâ mol â1

Topic: Chemistry, Chemical Kinetics, JEE Main
What is the acute angle between the lines $\mathrm{Ax}+\mathrm{By}=\mathrm{A}+\mathrm{B}$ and $A(x-y)+B(x+y)=2 B ?$

Options:
A $45^{\circ}$
B $\tan ^{-1}\left(\frac{A}{\sqrt{A^{2}+B^{2}}}\right)$
C $30^{\circ}$
D $60^{\circ}$

The correct answer is:
$45^{\circ}$

Solution:
Lines are $L_{1} \equiv A x+B y=A+B$ and $L_{2} \equiv A(x-y)+B(x+y)=2 B$
Slope of $L_{1}$ is $-\frac{A}{B}$
$\mathrm{m}_{1}=-\frac{\mathrm{A}}{\mathrm{B}} \quad\left[\mathrm{m}_{1}\right.$ is the side of line $\left.\mathrm{L}_{1}\right]$
For line $\mathrm{L}_{2}$ :
$\mathrm{Ax}-\mathrm{Ay}+\mathrm{Bx}+\mathrm{By}=2 \mathrm{~B}$
$(\mathrm{A}+\mathrm{B}) \mathrm{x}-(\mathrm{A}-\mathrm{B}) \mathrm{y}=2 \mathrm{~B}$
Slope of line $L_{2}$ in $\frac{(A+B)}{A-B}$
$\mathrm{m}_{2}=\frac{(\mathrm{A}+\mathrm{B})}{(\mathrm{A}-\mathrm{B})} \quad\left[\mathrm{m}_{2}\right.$ is the slope of line $\left.\mathrm{L}_{2}\right]$
If angle between line $\mathrm{L}_{1}$ and $\mathrm{L}_{2}$ is $\theta$ then
$\tan \theta=\frac{\mathrm{m}_{1}-\mathrm{m}_{2}}{1+\mathrm{m}_{1} \mathrm{~m}_{2}}$
$=\frac{-\frac{A}{B}-\frac{A+B}{A-B}}{1+\left(-\frac{A}{B}\right) \times\left(\frac{A+B}{A-B}\right)}=\frac{\frac{-A(A-B)-B(A+B)}{B(A-B)}}{\frac{B(A-B)-A(A+B)}{B(A-B)}}$
$=\frac{-A^{2}+A B-A B-B^{2}}{A B-B^{2}-A^{2}-A B}=\frac{-B^{2}-A^{2}}{-B^{2}-A^{2}}=1$
so, $\theta=\frac{\pi}{4}$

Topic: Mathematics, Straight Lines, JEE Main
What is the advantage of sexual reproduction over asexual reproduction?

Options:
A Asexual reproduction preserves genetic information
B Sexual reproduction provides variation
C Sexual reproduction is not as beneficial to the organism
D Asexual reproduction is more efficient

The correct answer is:
Sexual reproduction provides variation

Solution:
The main advantage of sexual reproduction over asexual reproduction is that it provides opportunities for variations and formulation of unique combinations of genetic setup, some of which may be beneficial to the organism as well as the population.

Topic: Biology, Biotechnology - Principles and Processes, NEET
What is the advantage of using a thermostable DNA polymerase in PCR?

Options:
A It allows for large-scale production
B It remains active during the high temperature induced denaturation of double stranded DNA
C It provides optimal growth conditions
D It enables cloning of foreign genes

The correct answer is:
It remains active during the high temperature induced denaturation of double stranded DNA

Solution:
The advantage of using a thermostable DNA polymerase in PCR is that it remains active during the high temperature induced denaturation of double stranded DNA, allowing for repeated amplification of the segment of DNA.

Topic: Biology, Biotechnology - Principles and Processes, NEET
What is the amount of CaCl2 in grams (i = 2.47) dissolved in 2.5 L of water such that its osmotic pressure is 0.75 atm at 27oC.?
Report your answer up to one decimal place.

Options:

The correct answer is:
3.4

Solution:
According to van't Hoff equation
Osmotic pressure π = i CRT = in B RT V
i = 2.47; V = 2.5 L; R = 0.0821 L atm K-1 mol-1
T = 27 + 273 = 300 K; π = 0.75 atm
n B = π V iRT
= 0.75 atm × 2.5 L 2.47 × 0.0821 L atm K - 1 mol - 1 × 300 K = 0.0308 mol
Amount of CaCl2 dissolved = nB × MB
= (0.0308 mol) × (111 g mol-1)
= 3.42 g

Topic: Chemistry, Solutions, JEE Main
What is the amount of heat required (in calories) to convert 10 g of ice at -10 â into steam at 100 â? Given that latent heat of vaporization of water is 540 cal g-1, latent heat of fusion of ice is 80 cal g-1, the specific heat capacity of water and ice are 1 cal g-1 Â°C-1 and 0.5 cal g-1 Â°C-1 respectively.

Options:

The correct answer is:
7250

Solution:
10 g of ice at -10â to ice at 0â
Q1=cm, âÎ¸=0.5Ã10Ã10=50 cal
10 g of ice 0â to water at 0â
Q2=mL=10Ã80=800 cal
10 g of water at 0â to water at 100â
Q3=cm, âÎ¸=1Ã10Ã100=1000 cal
10 g water at 100â to steam at 100â
Q4=mL=10Ã540=5400 cal
Total heat required, Q=Q1+Q2+Q3+Q4
= 50+800+1000+5400 = 7250 cal

Topic: Physics, Thermodynamics, JEE Main
What is the amplitude of the electric field in a parallel beam of light intensity $\left(\frac{15}{\pi}\right) \frac{\mathrm{W}}{\mathrm{m}^2}$ ? $\left[\right.$ Assume,$\left.\frac{1}{4 \pi \varepsilon_0}=9 \times 10^9 \frac{\mathrm{Nm}^2}{\mathrm{C}^2}\right]$

Options:
A $60 \mathrm{~N} / \mathrm{C}$
B $50 \mathrm{~N} / \mathrm{C}$
C $40 \mathrm{~N} / \mathrm{C}$
D $30 \mathrm{~N} / \mathrm{C}$

The correct answer is:
$60 \mathrm{~N} / \mathrm{C}$

Solution:
Intensity of parallel beam of light is given as
where, $E_0=$ amplitude of electric field.
Here,
$\begin{aligned}
I & =\frac{15}{\pi} \frac{\mathrm{W}}{\mathrm{m}^2}, \frac{1}{4 \pi \varepsilon_0}=9 \times 10^9 \frac{\mathrm{Nm}^2}{\mathrm{C}^2} \\
c & =3 \times 10^8 \mathrm{~ms}^{-1}
\end{aligned}$
From Eq. (i), we get
$\begin{aligned}
& E_0^2=\frac{2 \times I}{\varepsilon_0 \times c}=\frac{2 \times 4 \pi \times I}{4 \pi \varepsilon_0 \times c}=\left(\frac{2 \times 4 \pi \times \frac{15}{\pi} \times 9 \times 10^9}{3 \times 10^8}\right) \\
\Rightarrow & E_0^2=3600 \Rightarrow E_0=60 \mathrm{~N} / \mathrm{C}
\end{aligned}$

Topic: Physics, Electromagnetic Waves, JEE Main
What is the angle between $\vec{P}$ and the resultant of $(\vec{P}+\vec{Q})$ and $(\vec{P}-\bar{Q})$

Options:
A Zero
B $\tan ^{-1}(P / Q)$
C $\tan ^{-1}(Q / P)$
D $\tan ^{-1}(P-Q) /(P+Q)$

The correct answer is:
Zero

Solution:
Resultant $\vec{R}=\vec{P}+\vec{Q}+\vec{P}-\vec{Q}=2 \vec{P}$
$\therefore$ Angle between $\vec{P}$ and $2 \vec{P}$ is zero

Topic: Physics, Mathematics in Physics, JEE Main
What is the angle of dip at magnetic poles of earth?

Options:
A Zero
B $45^{\circ}$
C $90^{\circ}$
D $180^{\circ}$

The correct answer is:
$90^{\circ}$

Solution:
- The angle of dip is perpendicular to the Earth's surface at the magnetic poles. It is the angle created by the Earth's magnetic field. It is very important because it defines the Earth's magnetic field element.
- The angle of dip at any place is defined as the angle created by the earth's total magnetic field $B_0$ with the horizontal direction in the magnetic meridian.
- It is different at different places on the surface of the earth.
- The angle created with the horizontal by the Earth's magnetic field lines is called magnetic dip, dip angle, or magnetic inclination.
- The dip needle relaxes horizontally so that the angle of dip is zero at the magnetic equator.
- The angle of dip is very important for defining the elements of Earth's magnetic field region.
- The dip needle rests vertically at the magnetic poles so that the angle of dip is $90^{\circ}$ at the magnetic poles of the earth.
- At all other places, the dip angle lies between $0^{\circ}$ and $90^{\circ}$.

Topic: Physics, Magnetic Properties of Matter, JEE Main