datavorous/entrance-exam-dataset huggingface dataset:
When 12H+ pass through F0âF1 particle, how many ATPs are produced?

Options:
A 6 ATP
B 4 ATP
C 8 ATP
D 10 ATP

The correct answer is:
6 ATP

Solution:
The energy released during the electron system is utilized in synthesizing ATP with the help of ATP synthase enzyme (complex V). This complex consists of two major components: F1 and F0. For each ATP produced, 2H+ pass through F0 from the intermembrane space to the matrix down the electrochemical proton gradient.

Topic: Biology, Respiration in Plants, NEET
When 0.15 kg of ice at 0°C is mixed with 0.30 kg of water at 50°C in a container, the resulting temperature is 6.7°C. What is the heat of fusion of ice?

Options:
A 1.67 × ${{10}^{5}}$J $k{{g}^{-1}}$
B 2.51 × ${{10}^{5}}$J $k{{g}^{-1}}$
C 3.34 × ${{10}^{5}}$ J $k{{g}^{-1}}$
D 4.68 × ${{10}^{5}}$ J $k{{g}^{-1}}$

The correct answer is:
3.34 × ${{10}^{5}}$ J $k{{g}^{-1}}$

Solution:
Correct Option is : (C)
3.34 × ${{10}^{5}}$ J $k{{g}^{-1}}$

Topic: Chemistry, Thermal Properties of Matter, NEET
When 20âg of naphthoic acid (C 11 H 8 O 2 ) is dissolved in 50âg of benzene
k f â=â1 .72 Kkg mol â1 , a freezing point depression of 2âK is observed. The van't Hoff factor (i) is

Options:
A 0.5
B 1
C 2
D 3

The correct answer is:
0.5

Solution:
Actual molecular weight of naphthoic acid (C 11 H 8 O 2 )â=â172
Molecular mass (calculated) =â 1000âÃâ k f âÃâw WâÃâ ÎT f
= 1000 × 1.72 × 20 50 × 2 =344
van't Hoff factor (i) = actual mol.wt. calculated mol.wt.  =  172 344
=0.5

Topic: Chemistry, Solutions, NEET
When 20 g of Naphthoic acid (C11H8O2) is dissolved in 50 g of benzene (Kf=1.72 Kkgmol-1) , a freezing point depression of 2 K is observed. The Van’t Hoff factor (i) is

Options:
A 1
B 3
C 0.5
D 2

The correct answer is:
0.5

Solution:
ΔTf=Kf×molality×i
2=1.72×20172×100050×i
i=0.5.

Topic: Chemistry, Solutions, NEET
When 100 g of water is supercooled to -10°C, due to some disturbance mechanized or otherwise, some of it suddenly freezes to ice. What will be the temperature of the resultant mixture and how much mass would freeze?

Options:
A Resultant mixture reaches -10°C. 12.5 g of ice and rest is water.
B Resultant mixture reaches -5°C. 25 g of ice and rest is water.
C Resultant mixture reaches 0°C. 12.5 g of ice and rest is water.
D Resultant mixture reaches 5°C. 25 g of ice and rest is water.

The correct answer is:
Resultant mixture reaches 0°C. 12.5 g of ice and rest is water.

Solution:
Correct Option is : (C)
Resultant mixture reaches 0°C. 12.5 g of ice and rest is water.

Topic: Chemistry, Thermal Properties of Matter, NEET
When 22.4 litres of H2g is mixed with 11.2 litres of Cl2g, each at STP, the moles of HClg formed is equal to

Options:
A 1 mol of HClg
B 2 mol of HClg
C 0.5 mol HClg
D 1.5 mol of HClg

The correct answer is:
1 mol of HClg

Solution:
H222.4 ltâ¡+Cl211.2 ltâ¡â2HCl
1 mole=12mole
Limiting reagent is Cl2. So, 1 mole HCl is formed.

Topic: Chemistry, Some Basic Concepts of Chemistry, NEET, NEET 2014
When 22.4 litres of H2(g) is mixed with 11.2 litres of Cl2(g) , each at S.T.P., the moles of HCl (g) formed is equal to

Options:
A 1 mol of HCl (g)
B 0.5 mol of HCl (g)
C 2 mol of HCl (g)
D 1.5 mol of HCl (g)

The correct answer is:
1 mol of HCl (g)

Solution:
nH2=V(L)22.4L=22.422.4=1
nCl2=11.222.4=0.5 mole

Topic: Chemistry, Some Basic Concepts of Chemistry, NEET
When 24.8 keV X-rays strike a material, the photoelectrons emitted from K shell are observed to move in a circle of radius 23 mm in a magnetic field of 2Ã10-2 T. The binding energy of K shell electrons is

Options:
A 6.2 keV
B 5.4Â keV
C 7.4Â keV
D 8.6Â keV

The correct answer is:
6.2 keV

Solution:
evB=mv2R
⇒v=emBR
Kinetic energy of photoelectrons
K=12mv2=e2B2R22m
K=2.97×10-15J=18.6 KeV
K=EP-EK
EK=EP-K=24.8-18.6=6.2 KeV

Topic: Physics, Nuclear Physics, NEET
When 3.06 g of solid NH 4 HS is introduced into a two litre evacuated flask at 27Â°C,â30% of the solid decomposes into gaseous ammonia and hydrogen sulphide.

The values of K c and K p for the reaction at 27Â°C respectively will be:

Options:
A

8.1× 10 −4 and 3.9× 10 −2

B

0.8× 10 −5 and 4.9× 10 −5

C

9.1× 10 −3 and 4.9× 10 −3

D

8.1Ã 10 â5 and 4.9Ã 10 â2

The correct answer is:

8.1Ã 10 â5 and 4.9Ã 10 â2

Solution:
NH 4 HS( s )ââââââââââN H 3 (g)+ H 2 S(g)

Initial moles 3.06 51 0 0

Moles at eq. 3.06 51 Ã 70 100 3.06 51 Ã 30 100 3.06 51 Ã 30 100

Given:

V = 2 litre,

T = 300K,

În=2â0=2

â´âââââ K c =[ N H 3 ][ H 2 S ]
K c = 3.06Ã30 51Ã100Ã2 Ã 3.06Ã30 51Ã100Ã2 =8.1Ã1 0 -5 M 2 â

Also,

K p = K c ( RT ) În =8.1Ã 10 â5 ( 0.082Ã300 ) 2 =4.90Ã 10 â2 atm 2

Addition of more NH 4 HS on this equilibrium will cause no effect because concentration of NH 4 HS is not involved in formula of K p and K c .

Topic: Chemistry, Chemical Equilibrium, NEET
When 9.65 C of electricity is passed through a solution of silver nitrate (atomic weight of Ag = 107.87 taking as 108), the amount of silver deposited is

Options:
A 5.8 mg
B 10.8 mg
C 15.8 mg
D 20.8 mg

The correct answer is:
10.8 mg

Solution:
wAg=EAgÃ Q96500=108Ã9.6596500=1.08Ã10-2 g=10.8mg

Topic: Chemistry, Electrochemistry, NEET
When a 1 cm thick surface is illuminated with light of wavelength λ, the stopping potential is V0. When the same surface is illuminated by the light of wavelength 3λ, the stopping potential is V06. The threshold wavelength for the metallic surface is

Options:
A 4λ
B 5λ
C 3λ
D 2λ

The correct answer is:
5λ

Solution:
Let λ0 be threshold wavelength,
eV0=hc1λ-1λ0
Also,
eV06=hc13λ-1λ0
∴ 161λ-1λ0=13λ-1λ0
1λ01-16=1λ13-16
56λ0=16λ
λ0=5λ

Topic: Physics, Dual Nature of Matter, NEET
When a 10 Î¼C charge is enclosed by a closed surface, the flux passing through the surface is Ï. Now another 10 Î¼C charge is placed inside the closed surface, then the flux passing through the surface is ______.

Options:
A 4ϕ
B ϕ
C 2ϕ
D Zero

The correct answer is:
2ϕ

Solution:
Electric flux =qincε0
ϕ=10 μCε0
If more 10 μC charge is placed.
Electric flux =20 μCε0=2ϕ

Topic: Physics, Electrostatics, NEET
When a 20 mL of 0.08 M weak base BOH is titrated with 0.08 HCl, the pH of the solution at the end point is 5. What will be the pOH if 10 mL of 0.04 M NaOH is added to the resulting solution ? [Given : log 2 = 0.30 and log 3 = 0.48]

Options:
A 5.40
B 4.92
C None of these
D 5.88

The correct answer is:
5.88

Solution:
BOH + HCl â¶ BCl + H 2 O Initial 1 . 6 mM 1 . 6 mM 0 0 0 0 1 . 6 mM 1 . 6 mM
Total volume = 40 mL
[BCl] = 1.6/40 = 0.04M
p H = 1 2 p K w - p K b - log C
5 = 1 2 1 4 - p K b - log 0 . 0 4
pKb = 5.4
BCl + NaOH â¶ BOH + NaCl 1 . 6 mM 0 . 4 mM 0 0 - 0 . 4 mM - 0 . 4 mM + 0 . 4 mM + 0 Â· 4 mM --------------- --------------- --------------- --------------- 1 Â· 2 mM 0 0 . 4 mM 0 . 4 mM
p OH = p K b + log B + BOH
=5.4+log 1.2 0.4
= 5.4 + log 3
= 5 . 4 + 0 . 4 8
= 5 . 8 8

Topic: Chemistry, Ionic Equilibrium, NEET
When a bar magnet is placed at 90o to uniform magnetic field, it is acted upon by a couple which is maximum. For the couple to be half of the maximum value, it is to be inclined to the magnetic field at an angle is

Options:
A 30o
B 45o
C 60o
D 90o

The correct answer is:
30o

Solution:
When bar magnet is palced in external magnetic field it experiences torque.
Ï=MBsinâ¡Î¸
Ïmax =MB
Ï=MB2
âSinÎ¸=12
Î¸=30Â°

Topic: Physics, Magnetic Properties of Matter, NEET
When a bar magnet of magnetic moment m and moment of inertia I (about the center, perpendicular to the length) is cut into two equal pieces perpendicular to the length, what would be the period T' for each piece, if T is the period of oscillations of the original magnet about an axis through the midpoint, perpendicular to the length, in a magnetic field B?

Options:
A T' = T
B T' = 2T
C T' = T/2
D T' = 2T/m

The correct answer is:
T' = T/2

Solution:
Correct Option is : (C)
T' = T/2

Topic: Chemistry, Magnetic Properties of Matter, NEET
When a biconvex lens of glass having refractive index 1.47 is dipped in a liquid, it acts as a plane sheet of glass. This implies that the liquid must have refractive index

Options:
A equal to that of glass
B less than one
C greater than that of glass
D less than that of glass

The correct answer is:
equal to that of glass

Solution:
If biconvex lens behave like plane sheet, ray will pass undeviated through it only when medium has same refractive index as that of biconvex lens.

Topic: Physics, Ray Optics, NEET, NEET 2012 (Screening)
When a bio-chemical reaction is carried out in laboratory, outside the human body in absence of enzyme, then rate of reaction obtained is 10-6 times, the activation energy of reaction in the presence of enzyme is

Options:
A -6 RT
B +6 RT
C -6 (2.303) RT
D +6 (2.303) RT

The correct answer is:
-6 (2.303) RT

Solution:
We know that,
Rate of reaction(K) =Ae-E/RT ...(i)
And, 106.K=Ae-Ec/RT ...(ii)
By dividing equation (ii) by (i)
106.KK=Ae-Ec/RTAe-E/RT
10 6 = e E− E c /RT
6.ln10=(E-Ec)/RT
E-EcRT=2.303Ã6
E-Ec=6Ã2.303RT
or ÎEa=Ec-E=-6Ã2.303RT

Topic: Chemistry, Chemical Kinetics, NEET
When a block of mass m is displaced from its equilibrium position by a distance x towards the right, and two identical springs of spring constant K are attached to the block and fixed supports as shown in Figure 14.8, what is the restoring force acting on the block?

Options:
A Kx towards left
B 2Kx towards left
C Kx towards right
D 2Kx towards right

The correct answer is:
2Kx towards left

Solution:
Correct Option is : (B)
2Kx towards left

Topic: Chemistry, Oscillations, NEET
When a block of mass M is suspended by a long wire of length L, the length of the wire becomes L+l. The elastic potential energy stored in the extended wire is

Options:
A Mgl
B MgL
C 12Mgl
D 12 MgL

The correct answer is:
12Mgl

Solution:
12Kl2= energy
Kl=Mg
K=Mgl
∴ Energy =12 Kl2=12Mgl l2
=Mgl2

Topic: Physics, Mechanical Properties of Solids, NEET, NEET 2019 (All India)
When a body slides down an inclined plane with coefficient of friction as μk, then its acceleration is given by

Options:
A gμksin⁡θ+cos⁡θ
B gμksin⁡θ-cos⁡θ
C gsin⁡θ+μkcos⁡θ
D gsin⁡θ-μkcos⁡θ

The correct answer is:
gsin⁡θ-μkcos⁡θ

Solution:
F=mgsin⁡θ-μkcos⁡θ
a=gsin⁡θ-μkcos⁡θ

Topic: Physics, Laws of Motion, NEET
When a brown compound of manganese (A) is treated with HCl, it gives a gas (B). The gas taken in excess, reacts with NH3 to give an explosive compound (C). Identify compounds A, B, and C.

Options:
A A = MnO2, B = H2, C = NH4NO3
B A = Mn2O7, B = Cl2, C = NH4ClO4
C A = MnO2, B = Cl2, C = NH4ClO4
D A = MnO2, B = Cl2, C = NCl3

The correct answer is:
A = MnO2, B = Cl2, C = NCl3

Solution:
Correct Option is : (D)
A = MnO2, B = Cl2, C = NCl3

Topic: Chemistry, d and f Block Elements, NEET
When a carrier protein facilitates the movement of two molecules across the membrane in same direction, it is called :

Options:
A Uniport
B Transport
C Antiport
D Symport

The correct answer is:
Symport

Solution:
Above condition is called Symport in which the two molecules are moving in the same direction. This is a type of Facilitated diffusion of non-Polar substance from plasma membrane.

Topic: Biology, Transport in Plants, NEET, NEET 2022 (Phase 2)
When a ceiling fan is switched off, its angular velocity falls to half while it makes 36 rotations. How many rotations will it make before coming to rest?

Options:
A 24
B 36
C 18
D 12

The correct answer is:
12

Solution:
From third equation of angular motion,
Ï2=Ï02-2Î± (Here,Ï=Ï02,Î¸=36Ã2Ï)
â´ Ï022=Ï02-2Î±Ã36Ã2Ï
or 4Ã36ÏÎ±=Ï02-Ï024
or 4Ã36ÏÎ±=3Ï024
or Î±=Ï0216Ã12Ï ...(i)
According to question again applying the third equation of angular motion
Ï2=Ï02-2Î±Î¸ (Here, Ï=0)
â´ 0=Ï022-2ÃÏ02.Î¸16Ã12Ï
or Î¸=24Ï or Î¸=12Ã2Ï
But 2Ï=1 cycle
So, Î¸=12 cycle

Topic: Physics, Rotational Motion, NEET
When a ceiling fan is switched off, its angular velocity falls to half while it makes 36 rotations. How many rotations will it make before coming to rest?

Options:
A 24
B 36
C 18
D 12

The correct answer is:
12

Solution:
From the third equation of angular motion,
ω2=ω02-2αθ (Here,ω=ω02,θ=36×2π)
∴ ω022=ω02-2α×36×2π
or 4×36πα=ω02-ω024
or 4×36πα=3ω024
or α=ω0216×12π ...(i)
According to question again applying the third equation of angular motion
ω2=ω02-2αθ (Here, ω=0)
∴ 0=ω022-2×ω02.θ16×12π
or θ=24π or θ=12×2π
But 2π=1 cycle
So, θ=12 cycle

Topic: Physics, Rotational Motion, NEET
When a ceiling fan is switched off, its angular velocity reduces to 50% while it makes 36 rotations. How many more rotations will it make before coming to rest? (Assume uniform angular retardation)

Options:
A 18
B 12
C 36
D 48

The correct answer is:
12

Solution:
ω022=ω02-2αθ1⇒2αθ1=34ω02 ....(i)
0=ω022-2αθ2⇒2αθ2=ω024 ...(ii)
From (i) & (ii) θ1θ2=3
⇒θ2=θ13=363=12 rotations

Topic: Physics, Rotational Motion, NEET
When a ceiling fan is switched on, it makes 10 rotations in the first 4 s. Assuming uniform angular acceleration, the number of rotations it will make in the next 4 s is

Options:
A 10
B 20
C 40
D 40

The correct answer is:
40

Solution:
Î¸=2Ïn=Ï0t+12Î±t2
2ÏÃ10=12 Î±42 or Î±=40Ï16
Let it make N rotations in the first 8 s
Then, 2ÏN=12Î± 82
or N=12ÏÃ642Ã40Ï16=40
â´ The required number of rotations
=40-10=30

Topic: Physics, Laws of Motion, NEET
When a cell is placed in the solution of different concentration then, the cell swells in ______ and shrink in _______ respectively.

Options:
A hypotonic solution and isotonic solution
B hypotonic solution and hypertonic solution
C isotonic solution and hypertonic solution
D hypertonic solution and hypotonic solution

The correct answer is:
hypotonic solution and hypertonic solution

Solution:
When a cell is placed in a hypotonic solution or solution with lower concentration of ions then the endosmosis occurs and the cell swells due to entry of water. When a cell is placed in a hypertonic solution or solution with higher ionic concentration then the exosmosis will occur and the cell shrinks.

Topic: Biology, Transport in Plants, NEET
When a certain metallic surface is illuminated with monochromatic light of wavelength λ, the stopping potential for photoelectric current is 3V0 and when the same surface is illuminated with light of wavelength 2λ, the stopping potential is V0. The threshold wavelength of this surface for photoelectric effect is

Options:
A 6λ
B 4λ
C λ4
D λ6

The correct answer is:
4λ

Solution:
Using photoelectric equation, hf-hf0=12mv2=eVs
Or hcλ-hcλ0=eVs
For the first case, hcλ-hcλ0=e3V0 ...(i)
For the second case, hc2λ-hcλ0=eV0 ...(ii)
Solving λ0=4λ

Topic: Physics, Dual Nature of Matter, NEET, NEET 2015 (Phase 1)
When a certain photosensitive surface is illuminated with a monochromatic light of frequency Î½, the stopping potential of the photo current is -V02. When the surface is illuminated by monochromatic light of frequency Î½2, the stopping potential is -V0. The threshold frequency for photoelectric emission is

Options:
A 5ν​3
B 3ν2
C 43ν
D 2ν

The correct answer is:
3ν2

Solution:
hÎ½â=W+V02e
hÎ½â2=W+V0e
On solving, we get, W=32h Î½â
âhÎ½â0=32h Î½â
âÎ½â0=32Î½â

Topic: Physics, Dual Nature of Matter, NEET
When a certain weight is suspended from a long uniform wire, its length increases by 1 cm. If the same weight is suspended from another wire of the same material and length but having a diameter half of the first one then the increase in length will be

Options:
A 0.5 cm
B 2 cm
C 4 cm
D 8 cm

The correct answer is:
4 cm

Solution:
Increase in length is given by,
l=FLAYâlâ1r2 ( FL and Y are constant)
l2l1=r1r22=22=4
â l2=4l1=4 cm

Topic: Physics, Mechanical Properties of Solids, NEET
When a charged particle moving with velocity v→ is subjected to a magnetic field of induction B→ , the force on it is non-zero. This implies that

Options:
A angle between v→ and B→ is either zero or 180o
B angle between v→ and B→ is necessarily 90o
C angle between v→ and B→ can have any value other than 90o
D angle between v→ and B→ can have any value other than zero and 180o

The correct answer is:
angle between v→ and B→ can have any value other than zero and 180o

Solution:
∵ F=qvBsin⁡θ
F=0 , if θ=0o or 180o

Topic: Physics, Magnetic Effects of Current, NEET
When a charged particle moving with velocity $\vec{v}$ is subjected to a magnetic field of induction $\vec{B}$, the force on it is non-zero. This implies that:

Options:
A angle between is either zero or $180^{\circ}$
B angle between is necessarily $90^{\circ}$
C angle between can have any value other than $90^{\circ}$
D angle between can have any value other than zero and $180^{\circ}$

The correct answer is:
angle between can have any value other than zero and $180^{\circ}$

Solution:
$$
\begin{aligned}
\vec{F} & =q(\vec{V} \times \vec{B}) \\
& =q v B \sin \theta
\end{aligned}
$$
Therefore when $\theta=0^{\circ}$ or $\theta=180^{\circ}$
$$
F=0
$$

Topic: Physics, Magnetic Effects of Current, NEET, NEET 2006
When a charged particle moving with velocity v â is subjected to a magnetic field of induction B â , the force on it is non-zero. This implies that

Options:
A angle between v → and B → is either zero or 180Â°
B angle between v â and B â is necessarily 90Â°
C angle between v â and B â can have any value other than 90Â°
D angle between v â and B â can have any value other than zero and 180Â°

The correct answer is:
angle between v → and B → can have any value other than zero and 180°

Solution:
âµâF=qvBâsinÎ¸
∴ F=0, if θ=0° or 180°

Topic: Physics, Magnetic Effects of Current, NEET
When a chromite ore (A) is fused with sodium carbonate in free excess of air and the product is dissolved in water, a yellow solution of compound (B) is obtained. After treatment of this yellow solution with sulphuric acid, compound (C) can be crystallized from the solution. When compound (C) is treated with KCl, orange crystals of compound (D) crystallize out. Identify A to D and also explain the reactions.

Options:
A A]Sodium chromate (Na₂CrO₄), B] Potassium chromate (K₂CrO₄), C] Chromic acid (H₂CrO₄), D] Potassium dichromate (K₂Cr₂O₇)
B A] Chromite ore (FeCr₂O₄), B] Sodium chromate (Na₂CrO₄), C] Sodium dichromate (Na₂Cr₂O₇), D] Potassium dichromate (K₂Cr₂O₇)
C A] Potassium dichromate (K₂Cr₂O₇), B] Chromic acid (H₂CrO₄), C] Sodium chromate (Na₂CrO₄), D] Chromite ore (FeCr₂O₄)
D A] Chromic acid (H₂CrO₄), B] Potassium dichromate (K₂Cr₂O₇), C] Sodium chromate (Na₂CrO₄), D] Chromite ore (FeCr₂O₄)

The correct answer is:
A] Chromite ore (FeCr₂O₄), B] Sodium chromate (Na₂CrO₄), C] Sodium dichromate (Na₂Cr₂O₇), D] Potassium dichromate (K₂Cr₂O₇)

Solution:
Correct Option is : (B)
A] Chromite ore (FeCr₂O₄), B] Sodium chromate (Na₂CrO₄), C] Sodium dichromate (Na₂Cr₂O₇), D] Potassium dichromate (K₂Cr₂O₇)

Topic: Chemistry, d and f Block Elements, NEET
When a cold, dilute, aqueous solution of potassium permanganate is added to an alkene, what change in color is typically observed?

Options:
A Change to purple
B Change to green
C No change
D Change to brown

The correct answer is:
Change to purple

Solution:
When a cold, dilute, aqueous solution of potassium permanganate is added to an alkene, it typically changes from its initial color to purple as the permanganate ion is reduced during the oxidation of the alkene.

Topic: Chemistry, Hydrocarbons, NEET
When a copper ball is heated, the largest percentage increase will occur in its

Options:
A diameter
B area
C volume
D density

The correct answer is:
volume

Solution:
When a copper ball is heated, its size increases.
As, volume∝(radius)3 and area∝(radius)2
So percentage increase will be largest in its volume.

Topic: Physics, Thermal Properties of Matter, NEET
When a copper wire of length 2.2 m and a steel wire of length 1.6 m, both of diameter 3.0 mm, are connected end to end and stretched by a load, the net elongation is found to be 0.70 mm. What is the load applied?

Options:
A 3.6×${{10}^{2}}~N$
B 1.8×${{10}^{2}}~N$
C 1.8×${{10}^{3}}~N$
D 3.6×${{10}^{3}}~N$

The correct answer is:
1.8×${{10}^{2}}~N$

Solution:
Correct Option is : (B)
1.8×${{10}^{2}}~N$

Topic: Chemistry, Mechanical Properties of Solids, NEET
When a cross is made between offspring and its parents, it is known as

Options:
A Monohybrid cross
B Dihybrid cross
C Back cross
D Reciprocal cross

The correct answer is:
Back cross

Solution:
In plant breeding, the back cross is performed a few times in order to increase the traits of that parent. A test cross is a special type of back cross, where the F1 progeny is mated with a recessive parent.

Topic: Biology, Principles of Inheritance and Variation, NEET
When a diploid female plant is crossed with a tetraploid male, the ploidy of endosperm cells in the resulting seed is:

Options:
A tetraploidy
B pentaploidy
C diploidy
D triploidy.

The correct answer is:
tetraploidy

Solution:
Female parent genotype $=2 \mathrm{~N}=2 \mathrm{~A}$
Male Gamete formed $=\mathrm{N}=\mathrm{A}$
Male parent genotype $=2 \mathrm{~N}=4 \mathrm{~A}$
Male Gamete formed $=\mathrm{N}=2 \mathrm{~A}$
Endosperm is formed by the fusion of 2 polar nuclei (from female gamete) and 1 male gamete.
Thus, the ploidy of endosperm $=$ $3 \mathrm{~N}=\mathrm{A}+\mathrm{A}+2 \mathrm{~A}=4 \mathrm{~A}$ (tetraploid)

Topic: Biology, Cell Cycle and Cell Division, NEET, NEET 2004
When a diploid female plant is crossed with a tetraploid male, the ploidy of endosperm cells in the resulting seed is

Options:
A Tetraploidy
B Pentaploidy
C Diploidy
D Triploidy

The correct answer is:
Tetraploidy

Solution:
Endosperm is formed due to fusion of the haploid male gamete with the two polar nuclei of the embryo sac. But in this case the male plant is tetraploid so that its gametes would be diploid. When these diploid gametes fuse with two polar nuclei of the embryo sac the resultant endosperm would be tetraploid.

Topic: Biology, Sexual Reproduction in Flowering Plants, NEET
When a electron jumps from a higher energy state to a lower energy state with an energy difference of ΔE electron-volt, then the wavelength of the spectral line emitted is approximately

Options:
A 12375ÎE m
B 12375ÎEÂ nm
C 12375ÎE pm
D 12375 ΔE A∘

The correct answer is:
12375 ΔE A∘

Solution:
Energy, hν=ΔE electron volt.
⇒ hcλ=ΔE electron volt.
⇒ λ=hcΔE=6.6×10-34×3×108ΔE
But, 1 eV=16×10-19 J
∴ λ=6.6×10-34×3×108ΔE×16×10-19 m
⇒ λ=12375×10-10ΔE m
⇒ λ=12375ΔE A∘

Topic: Physics, Atomic Physics, NEET
When a electron jumps from a higher energy state to a lower energy state with an energy difference of ΔE electron-volt, then the wavelength of the spectral line emitted is approximately

Options:
A 12375ÎE m
B 12375ÎEÂ nm
C 12375ÎE pm
D 12375 ΔE Å

The correct answer is:
12375 ΔE Å

Solution:
Energy, hv=ÎE electron volt.
â hcÎ»=ÎE electron volt.
â Î»=hcÎE=6.6Ã10-34Ã3Ã108ÎE
But, 1eV=16Ã10-19 J
â´ Î»=6.6Ã10-34Ã3Ã108ÎEÃ16Ã10-19 m
â Î»=12375Ã10-10ÎE m
â Î»=12375ÎE â«

Topic: Physics, Atomic Physics, NEET
When a flower can be divided into two equal radial halves in any radial plane passing through the centre is known as ___.

Options:
A Actinomorphic
B Zygomorphic
C Trimerous
D Tetramerous

The correct answer is:
Actinomorphic

Solution:
When a flower can be divided into two equal radial halves in any radial plane passing through the centre is known as Actinomorphic.

Topic: Biology, Morphology of Flowering Plants, NEET
When a forward bias is applied to a p-n junction, it

Options:
A raises the potential barrier.
B reduces the majority carrier current to zero.
C lowers the potential barrier.
D None of the above.

The correct answer is:
lowers the potential barrier.

Solution:
Correct Option is : (C)
lowers the potential barrier.

Topic: Chemistry, Semiconductors, NEET
When a free neutron decays to form a proton and an electron, then choose the incorrect statement

Options:
A the relation may be expressed as

n10→ p11+ e0-1+v

B every electron comes out with the same energy
C the electron shares the major part of the energy released
D all the above

The correct answer is:
all the above

Solution:
n10â p11+ e0-1+v

The electron comes out with a spectrum of energies. The energy released is shared between electron and neutrino.

Topic: Physics, Nuclear Physics, NEET