datavorous/entrance-exam-dataset huggingface dataset:
In a single slit diffraction pattern, the distance between the first minimum on the left and the first minimum on the right is 5 mm. The screen on which the diffraction pattern is displayed is at a distance of 80 cm from the slit. The wavelength is 6000 â«. The slit width in mm is about

Options:
A 0.576
B 0.348
C 0.192
D 0.096

The correct answer is:
0.192

Solution:
Slit width, w=Dλd
Given, D=80 cm=80×10-2 m
λ=6000 Å=6000×10-10 m
d=52 mm=52×10-3 m
∴ w=80×10-2×6000×10-10×25×10-3
w=0.192×10-3 m=0.192 mm

Topic: Physics, Wave Optics, NEET
In a solid ‘AB’ having the NaCl structure, ‘A’ atoms occupy the corners of the cubic unit cell. If all the face centered atoms along one of the axes are removed, then the resultant stoichiometry of the solid is:

Options:
A AB2
B A2B
C A4B3
D A3B4

The correct answer is:
A3B4

Solution:
A= 1 8 ×8 corner + 1 2 ×4 faces =3
B=1 centre + 1 4 ×12 edge =4
A3B4

Topic: Chemistry, Solid State, NEET
In a solid 'AB' having the NaCl structure, 'A' atoms occupy the corners of the cubic unit cell. If all the face centred atoms along one of the axes are removed, then the resultant stoichiometry of the solid is

Options:
A AB2
B A2B
C A4B3
D A3B4

The correct answer is:
A3B4

Solution:
Na in NaCl has eight corner and six face atoms and thus, if we remove face centred atom of one axis, then two face atoms are removed. Thus, A is at 8 corners & at 4 face centers.
Number of A atoms per unit cell =8×18+4×12=3
B present in all octahedral voids, hence
Number of B atoms per unit cell =12×14+1=4
Thus, formula is A3B4.

Topic: Chemistry, Solid State, NEET
In a solid sphere of mass M and radius R, a spherical cavity of radius R2 is made, such that the centre of cavity is at a distance R2 from the centre of the sphere. A point mass m is placed inside the cavity, at a distance R4 from the centre of the sphere. The gravitational pull between the sphere and the point mass m is

Options:
A 11GMmR2
B 14GMmR2
C GMm2R2
D GMmR2

The correct answer is:
GMm2R2

Solution:
The gravitational field inside the cavity is uniform and at the centre of the cavity, it can be calculated as

Ecavity-Ecentre=GMR3R2-0=GM2R3

F=GMm2R3

Topic: Physics, Gravitation, NEET
In a solution, the decrease in the vapor pressure of a solvent is primarily influenced by what factor?

Options:
A The nature of the solute
B The temperature
C The quantity of the non-volatile solute
D The pressure of the surroundings

The correct answer is:
The quantity of the non-volatile solute

Solution:
The paragraph indicates that the decrease in vapor pressure in a solution is influenced primarily by the quantity of the non-volatile solute.

Topic: Chemistry, Solutions, NEET
In a species, the weight of the newborn ranges from 2 to 5 kg. 97% of the newborn with an average weight between 3 and 3.3 kg survive whereas 99% of the infants born with weights from 2 to 2.5 kg or 4.5 to 5 kg die. Which type of selection process is taking place?

Options:
A Directional Selection
B Stabilizing Selection
C Disruptive Selection
D Cyclical Selection

The correct answer is:
Stabilizing Selection

Solution:
Stabilizing selection (not to be confused with negative or purifying selection) is a type of natural selection in which the population mean stabilizes on a particular non-extreme trait value. Karn & Penrose (1951) showed that birth weight follows a normal distribution, that mortality for newborns is greater for those either under- or over-weight, and that the mean birth weight (7 lbs) coincides with that showing minimum mortality. That is, natural selection reduces the variance in birth weight, in such a way that the distribution has become stabilized around the optimum size for maximum survival.

Topic: Biology, Evolution, NEET, NEET 2019 (All India)
In a square planar complex, what is the maximum number of ligands that can be arranged in a cis isomer?

Options:
A 1
B 2
C 3
D 4

The correct answer is:
2

Solution:
In a square planar complex, the maximum number of ligands that can be arranged in a cis isomer is 2.

Topic: Chemistry, Coordination Compounds, NEET
In a stationary wave represented by y=2acoskxsinÏt the intensity at a certain point is maximum when

Options:
A

coskx is maximum

B

coskx is minimum

C

sinωt is maximum

D

sinωt is minimum

The correct answer is:

coskx is maximum

Solution:
Intensityâamplitude2
â2acosâ¡kx2
Hence, intensity will be maximum when cos kx is maximum.

Topic: Physics, Waves and Sound, NEET
In a system of two polarisers, it is found that the intensity of light from the second polarizer is half from that of the first polariser. The angle between their pass axes is

Options:
A 60°
B 30°
C 0°
D 45°

The correct answer is:
45°

Solution:
According to Malus law,
I=I0cos2⁡θ
Here, I=I02
Now, I02=I0cos2⁡θ
⇒ cos2⁡θ=12
⇒ cos⁡θ=12
⇒ θ=cos-1⁡12=45°

Topic: Physics, Wave Optics, NEET
In a system where (n-1) equal point masses each of mass m are placed at the vertices of a regular n-polygon, while the vacant vertex has a position vector a with respect to the center of the polygon, what is the position vector of the center of mass?

Options:
A $\frac{1}{n-1}a$
B $\frac{1}{1-n}a$
C $\frac{1}{1-{{n}^{2}}}a$
D $\frac{1}{{{n}^{2}}-1}a$

The correct answer is:
$\frac{1}{1-n}a$

Solution:
Correct Option is : (B)
$\frac{1}{1-n}a$

Topic: Chemistry, Rotational Motion, NEET
In a terrestrial ecosystem, what is the food chain that carries a larger fraction of energy?

Options:
A Grazing food chain
B Detritus food chain
C Photosynthetic food chain
D Omnivores food chain

The correct answer is:
Detritus food chain

Solution:
In a terrestrial ecosystem, a much larger fraction of energy flows through the detritus food chain than through the grazing food chain.

Topic: Biology, Ecosystem, NEET
In a terrestrial ecosystems such as forests, maximum energy is found in

Options:
A T1
B T2
C T3
D T4

The correct answer is:
T1

Solution:
T1 or first tropic level in a terrestrial ecosystem is occupied by producers, which trap solar energy and transfer it to successive tropic level. Maximum energy is always present in T1 .

Topic: Biology, Ecosystem, NEET
In a testcross involving F1 dihybrid flies, more parental-type offspring were produced than the recombinant-type offspring. This indicates:

Options:
A The two genes are located on two different chromosomes
B Chromosomes failed to separate during meiosis
C The two genes are linked and present on the same chromosome
D Both of the characters are controlled by more than one gene

The correct answer is:
The two genes are linked and present on the same chromosome

Solution:
If a plant with genotype AaBb is crossed with that with aabb, then independent assortment would result in the production of 4 types of offsprings in equal proportion.
AaBb - gametes: AB Ab aB ab
Aabb - gametes: ab ab ab
Offspring according to independent assortment:
AaBb Aabb aaBb aabb
1 : 1 : 1 : 1
(Parental) (Recombinants) (Parental)
Since parental percentage is more than recombinants, it is due to linkage between genes A and B.

Topic: Biology, Principles of Inheritance and Variation, NEET, NEET 2016 (Phase 1)
In a testcross involving F1 dihybrid flies, more parental-type offspring were produced than the recombinant-type offspring. This indicates:

Options:
A The two genes are located on two different chromosomes
B Chromosomes failed to separate during meiosis
C The two genes are linked and present on the same chromosome
D Both of the characters are controlled by more than one gene

The correct answer is:
The two genes are linked and present on the same chromosome

Solution:
If a plant with genotype AaBb is crossed with that with aabb, then independent assortment would result in the production of 4 types of offsprings in equal proportion.
AaBb - gametes: AB Ab aB ab
Aabb - gametes: ab ab ab
Offspring according to independent assortment:
AaBb Aabb aaBb aabb
1 : 1 : 1 : 1
(Parental) (Recombinants) (Parental)
Since parental percentage is more than recombinants, it is due to linkage between genes A and B.

Topic: Biology, Principles of Inheritance and Variation, NEET
In a thermochemical equation, what do the coefficients refer to?

Options:
A The number of molecules of reactants and products involved in the reaction.
B The number of moles of reactants and products involved in the reaction.
C The physical state of the substances involved.
D The temperature and pressure conditions of the reaction.

The correct answer is:
The number of moles of reactants and products involved in the reaction.

Solution:
In a thermochemical equation, the coefficients refer to the number of moles (never molecules) of reactants and products involved in the reaction.

Topic: Chemistry, Thermodynamics (C), NEET
In a thermodynamic process, 200 J of heat is given to a gas and 100 J of work is also done on it. The change in internal energy of the gas is

Options:
A 100 J
B 300 J
C 419 J
D 24 J

The correct answer is:
300 J

Solution:
ΔQ=ΔU+ΔW

Given, ΔQ=200 J and ΔW=-100 J
⇒ΔU=ΔQ-ΔW
⇒ΔU=200--100=300 J

Topic: Physics, Thermodynamics, NEET
In a thermodynamic process, temperature and volume of one mole of an ideal monatomic gas are varied according to the relation VT=k, where k is a positive constant. In this process, if the temperature of the gas increases by ∆T, then the amount of heat absorbed by gas is [R is the universal gas constant]

Options:
A 12R∆T
B 32RΔT
C 23RΔT
D 13RΔT

The correct answer is:
12R∆T

Solution:
VT=K
From ideal gas equation pv=nRT

PV2=Constant

For polytrophic =w=P1V1-P2V2x-1=nRT1-T2x-1=-nRÎT2-1=-nRÎT

Q=Îu+w

Q=32RΔT-nRΔT=12RΔT

Topic: Physics, Thermodynamics, NEET
In a transcription unit, the promoter is located towards

Options:
A 5' end of the structural gene
B 3' end of the structural gene
C 5' end of the structural gene
D 3' end of the coding strand

The correct answer is:
5' end of the structural gene

Solution:
A transcription unit consists of a promoter, a structural gene, and a terminator. The promoter is said to be located towards 5' end (upstream) of the structural gene, the reference is made with respect to the polarity of the coding strand.

Topic: Biology, Molecular Basis of Inheritance, NEET
In a transistor

Options:
A emitter is more highly doped than collector
B collector is more highly doped than emitter
C both are equally doped
D none of these

The correct answer is:
emitter is more highly doped than collector

Solution:
The emitter is highly doped than collector and base is least doped.

Topic: Physics, Semiconductors, NEET
In a transistor, the emitter, base and collector are respectively

Options:
A heavily doped, lightly doped, moderately doped
B heavily doped, moderately doped, lightly doped
C lightly doped, moderately doped, heavily doped
D none

The correct answer is:
heavily doped, lightly doped, moderately doped

Solution:
emitter heavily doped as compared to collector so that charge carrier propagates from emitter to collector.

Topic: Physics, Semiconductors, NEET
In a transistor

Options:
A emitter is more highly doped than collector
B collector is more highly doped than emitter
C both emitter and collector are equally doped
D None of these

The correct answer is:
emitter is more highly doped than collector

Solution:
Emitter is highly doped than collector and base is least doped.

Topic: Physics, Semiconductors, NEET
In a transverse progressive wave of amplitude A, the maximum particle velocity is four times its 'wave velocity' then the wavelength of the wave is

Options:
A 2 π A
B π A
C π A 2
D π A 4

The correct answer is:
π A 2

Solution:
Given, Amplitude of the wave = A
Maximum velocity of particle Vmax = 4v
(where v is the velocity of wave)
Maximum velocity of wave, vmax = 4v
or v max = A ω = 4 v
∴ ω = 4 V A
Wavelength of the wave,
λ = velocity of wave (v) frequency of wave (f) = v ω = 2 π v ω
= 2 π v 4 v / A = π A 2 ....(where, f = ω 2 π )

Topic: Physics, Waves and Sound, NEET
In a transverse section of a sunflower root:

Options:
A Both protoxylem and metaxylem vessels arepresent towards the periphery.
B Both protoxylem and metaxylem vessels arepresent towards the centre.
C The protoxylem vessels are present towardsthe centre and metaxylem vessels are presenttowards the periphery.
D The protoxylem vessels are present towards the periphery and metaxylem vessels are present towards the centre.

The correct answer is:
The protoxylem vessels are present towards the periphery and metaxylem vessels are present towards the centre.

Solution:
In a transverse section of a Sunflower root, Vascular bundles are described as radial and tetrarch. There are four bundles each of xylem and phloem occurring alternately and Xylem is exarch type. (In roots, the protoxylem lies towards periphery and metaxylem lies towards the centre. Such arrangement of primary xylem is called exarch).

Topic: Biology, Anatomy of Flowering Plants, NEET
In a trihybrid cross, the different types of genotypes obtained in the F2 generation is

Options:
A 8
B 18
C 27
D 36

The correct answer is:
27

Solution:
In a monohybrid cross, there are 3 types of genotypes produced in the F2 generation: AA, Aa, aa. In a dihybrid cross, there are 3Ã3=9 types of genotypes produced in the F2 generation: AABB, AaBB, aaBB, AABb, AaBb, aaBb, AAbb, Aabb, aabb. In a trihybrid cross, there are 3Ã3Ã3= 27 types of genotypes produced in the F2 generation (number of different F2 genotypes is 3n) and they are:

AABBCC, AaBBCC, aaBBCC, AABbCC, AaBbCC, aaBbCC, AAbbCC, AabbCC, aabbCC, AABBCc, AaBBCc, aaBBCc, AABbCc, AaBbCc, aaBbCc, AAbbCc, AabbCc, aabbCc, AABBcc, AaBBcc, aaBBcc, AABbcc, AaBbcc, aaBbcc, AAbbcc, Aabbcc, aabbcc.

Topic: Biology, Principles of Inheritance and Variation, NEET
In a turbulent flow, the velocity of the liquid in contact with the walls of the tube is

Options:
A zero
B maximum
C in between zero and maximum
D equal to critical velocity

The correct answer is:
equal to critical velocity

Solution:
In a turbulent flow, the velocity of the liquid in contact with the walls of the tube is equal is critical velocity.

Topic: Physics, Mechanical Properties of Fluids, NEET
In a two-celled pollen grain in angiosperms, the large cell with irregular nucleus

Options:
A divides and forms two male gametes
B divides and forms pollen tube
C does not divide but forms two male gametes
D does not divide but forms pollen tube

The correct answer is:
does not divide but forms pollen tube

Solution:
The two cells of a pollen grain are vegetative cell and generative cell. The generative cell is a small spindle-shaped cell, which floats in the cytoplasm of the larger cell with an irregular nucleus. The larger cell is called the vegetative cell. It germinates on the stigma. It absorbs the sugary secretion and the cytoplasm comes out as a pollen tube. It does not divide.

Topic: Biology, Sexual Reproduction in Flowering Plants, NEET
In a type of apomixis known as adventive embryony, embryos develop directly from the:

Options:
A nucellus or integuments
B zygote
C synergids or antipodals in an embryo sac
D accessory embryo sacs in the ovule.

The correct answer is:
nucellus or integuments

Solution:
In the adventivetype of polyembryony, embryos develop directly from the nucellus or integuments. It is seen in is seen in Citrus, Opuntia, and Mangifera.

Topic: Biology, Sexual Reproduction in Flowering Plants, NEET, NEET 2005
In a typical antibody, disulphide bonds are not seen in which of the following?

Options:
A between heavy chain and light chain
B between two heavy chains
C between two light chains
D within the heavy chain

The correct answer is:
between two light chains

Solution:
Antibodies or Immunoglobulins are produced by B- lymphocytes. A typical antibody has two heavy peptide chains and two light peptide chains. There are disulphide bonds within each light chain, within each heavy chain, between heavy chains and between one heavy and one light chains.

Topic: Biology, Human Health and Diseases, NEET
In a typical fuel cell, the reactants (R) and product (P) are :-

Options:
A R=H2(g),O2(g);P=H2O2(ℓ)
B R=H2(g),O2(g);P=H2O(ℓ)
C R=H2(g),O2(g),Cl2(g);P=HClO4(aq)
D R=H2(g),N2(g);P=NH3(aq)

The correct answer is:
R=H2(g),O2(g);P=H2O(ℓ)

Solution:
In typical fuel cell
Reactants =H2,O2
Products =H2O

Topic: Chemistry, Electrochemistry, NEET, NEET 2020 (Phase 2)
In a typical Mendelian cross which is a dihybrid cross, one parent is homozygous for both dominant traits and another parent is homozygous for both recessive traits. In the F2 generation, both parental combinations and recombinations appear. The phenotypic ratio of parental combinations to recombinations, is

Options:
A 10:6
B 12:4
C 9:7
D 15:1

The correct answer is:
10:6

Solution:
A cross of round yellow seeds (both dominant) and green wrinkled seed (both recessive) plants produced 9 : 3 : 3 : 1 ratio of plants (phenotypic) in F2 generation. The ratio of parental to recombinant is 10 : 6 here because the 9 and 1 are of parental type and 3 and 3 are recombinant.

Topic: Biology, Principles of Inheritance and Variation, NEET
In a typical Mendelian dihybrid cross, one parent is homozygous for both dominant traits and another parent is homozygous for both recessive traits. In the F2 generation, both parental combinations and recombinants type appear. The phenotypic ratio of parental combinations to recombinants is

Options:
A 15:1
B 12 :4
C 9:7
D 10:6

The correct answer is:
10:6

Solution:
When two pure pea plants one with yellow round seeds and one with green wrinkled seeds are crossed, all plants in the F1 generation have yellow round seeds. On selfing they will produced organisms with yellow round seeds, yellow wrinkled seeds, green round seeds and green wrinkled seeds in the ratio 9: 3: 3: 1 . Out of these yellow round seeds and green wrinkled seeds are parental combinations while yellow wrinkled seeds and green round seeds are recombinations. Thus the phenotypic ratio of parental combinations to recombinations is 10 :6

Topic: Biology, Principles of Inheritance and Variation, NEET
In a U-tube, the radii of two columns are, respectively r1 and r2. When a liquid of density ρθ=0° is filled in it, a level difference of h is observed on the two arms. The surface tension of the liquid is

Options:
A Ïghr1r22r2-r1
B hÏg r2- r1
C hÏg r2-r12
D hÏg2r2-r1

The correct answer is:
ρghr1r22r2-r1

Solution:
Ïgh=2T 1r1-1r2=2T r2-rlr1r2
â´ T=Ïghr1r22r2-r1

Topic: Physics, Mechanical Properties of Fluids, NEET
In a uniform circular motion, the centripetal acceleration is

Options:
A Towards the centre of the circular path and perpendicular to the instantaneous velocity
B Away from the centre of the circular path and perpendicular to the instantaneous velocity
C A variable acceleration making 45o with the instantaneous velocity
D A variable acceleration, parallel to the instantaneous velocity

The correct answer is:
Towards the centre of the circular path and perpendicular to the instantaneous velocity

Solution:
In uniform circular motion, the centripetal acceleration is towards the centre of the circular path and perpendicular to the instantaneous velocity.

Topic: Physics, Laws of Motion, NEET
In a uniform electric field, a point charge of mass m and charge q is released from rest. If there are no other forces acting on the particle, then which of the following graphs, correctly show the dependence of the particles speed v on the distance x travelled by it? [Graphs are schematic and not drawn to scale]

Options:
A
B
C
D

The correct answer is:

Solution:
Using work-energy theorem,

qEx=12mv2

⇒v2=2qEmx⇒v=2qEmx

Topic: Physics, Electrostatics, NEET
In a uniform magnetic field of 0.049 T , a magnetic needle performs 20 complete oscillations in 5 seconds as shown. The moment of inertia of the needle is $9.8 \times 10^{-6} \mathrm{~kg} \mathrm{~m}^2$. If the magnitude of magnetic moment of the needle is $x \times 10^{-5} \mathrm{Am}^2$, then the value of ' $x$ ' is :

Options:
A $128 \pi^2$
B $50 \pi^2$
C $1280 \pi^2$
D $5 \pi^2$

The correct answer is:
$1280 \pi^2$

Solution:
Time period of Oscillation, $T=2 \pi \sqrt{\frac{I}{M B}}$
$\begin{aligned}
& \Rightarrow \quad \frac{1}{4}=2 \pi \sqrt{\frac{9.8 \times 10^{-6}}{M \times 0.049}} \\
& \Rightarrow \frac{1}{16}=4 \pi^2 \times \frac{9.8 \times 10^{-6}}{M \times 49 \times 10^{-3}} \\
& \Rightarrow \quad M=\frac{4 \pi^2 \times 9.8 \times 10^{-6}}{49 \times 10^{-3}} \times 16 \\
& =\frac{4 \pi^2 \times 9.8 \times 16 \times 10^{-3}}{49} \\
& =12.8 \pi^2 \times 10^{-3} \times 10^{-2} \times 10^2 \\
& =1280 \pi^2 \times 10^{-5} \mathrm{Am}^2 \\
&
\end{aligned}$

Topic: Physics, Magnetic Effects of Current, NEET, NEET 2024
In a unilocular ovary with a single ovule, the placentation is

Options:
A axile
B marginal
C basal
D free central

The correct answer is:
basal

Solution:
Placentation is the arrangement of the ovules in the ovary and their attachment to it. Placentation are of various type in the angiosperms - marginal, axile, central, parietal, basal, and free central.
In marginal placentation, ovules are attached to the ridge formed on the ventral suture of the ovary without any locules. Pea plant has this arrangement. When the ovules are attached to the central column and the ovary wall forms chambers called locules separating the ovules from each other is said the axile placentation. In parietal, the ovules are attached to the inner wall or towards the periphery of the ovary. In basal placentation the ovules are attached at the base of the ovary with single locus or chamber. Free-central placentation is when the ovules are attached at the central axis of the ovary without any septa present like in axile pattern.

Topic: Biology, Morphology of Flowering Plants, NEET
In a u-tube as shown in a figure, water and oil are in the left side and right side of the tube respectively. The heights from the bottom for water and oil columns are $15 \mathrm{~cm}$ and $20 \mathrm{~cm}$ respectively. The density of the oil is $\left[\right.$ take $\left.\rho_{\text {water }}=1000 \mathrm{~kg} / \mathrm{m}^3\right]$

Options:
A $1200 \mathrm{~kg} / \mathrm{m}^3$
B $750 \mathrm{~kg} / \mathrm{m}^3$
C $1000 \mathrm{~kg} / \mathrm{m}^3$
D $1333 \mathrm{~kg} / \mathrm{m}^3$

The correct answer is:
$750 \mathrm{~kg} / \mathrm{m}^3$

Solution:
According to Pascal's law "Pressure applied to an enclosed fluid is transmitted undiminished to every point of the fluid and the walls of the containing vessel."
In the given situation as shown in the figure below
Pressure due to water column of height $15 \mathrm{~cm}=$ Pressure due to oil column of height $20 \mathrm{~cm}$
$$
\begin{aligned}
\Rightarrow \quad \mathrm{h}_{\mathrm{w}} \rho_{\mathrm{w}} \mathrm{g} & =\mathrm{h}_0 \rho_0 \mathrm{~g} \\
15 \rho_w & =20 \rho_0 \Rightarrow \rho_0=\frac{15}{20} \rho_\omega \\
\rho_0 & =\frac{15}{20} \times 1000\left(\because \text { given, } \rho_w=1000 \mathrm{~kg} \mathrm{~m}^{-3}\right) \\
& =750 \mathrm{kgm}^{-3}
\end{aligned}
$$

Topic: Physics, Mechanical Properties of Fluids, NEET, NEET 2019 (Odisha)
In a U-tube the radii of two columns are respectively r1 and r2 . When a liquid of density ρ , contact angle θ=0o is filled in it, a level difference of h is observed in the two arms, then the surface tension of the liquid is

Options:
A ρghr1r22(r2–r1)
B hρg(r2–r1)
C hρg(r2–r1)2
D hρg2(r2–r1)

The correct answer is:
ρghr1r22(r2–r1)

Solution:
Ïgh=2T1r1â1r2=2T r2ârlr1r2
â´T=Ïghr1r22(r2âr1)

Topic: Physics, Mechanical Properties of Fluids, NEET