datavorous/entrance-exam-dataset huggingface dataset:
A whistle revolves in a circle with angular speed $\omega=20 \mathrm{rad} \mathrm{s}^{-1}$ using a string of length $50 \mathrm{~cm}$. If the frequency of sound from the whistle is $385 \mathrm{~Hz}$, then what is the minimum frequency heard by an observer which is away from the centre $\left(v_{\text {sound }}=340 \mathrm{~ms}^{-1}\right)$ ?

Options:
A $385 \mathrm{~Hz}$
B $375 \mathrm{~Hz}$
C $394 \mathrm{~Hz}$
D $333 \mathrm{~Hz}$

The correct answer is:
$375 \mathrm{~Hz}$

Solution:
Velocity of source is given as
$$
\begin{gathered}
V_{\text {source }}=\text { rus }=0.5 \times 20 \\
=10 \mathrm{~ms}^{-1}
\end{gathered}
$$
$\therefore$ Minimum frequency is $f \mathrm{~min}$
$$
\begin{aligned}
& =\left(\frac{V}{V+V_s}\right) f \\
& =\frac{340}{340+10} \times 385=374 \mathrm{~Hz}
\end{aligned}
$$

Topic: Physics, Waves and Sound, NEET, NEET 2002
A white pea plant is crossed a heterozygous violet pea plant. What will be characteristic of offspring?

Options:
A 75 % recessive
B 50 % recessive
C 25 % recessive
D All dominant

The correct answer is:
50 % recessive

Solution:
In a typical test cross, an organism (pea plants here) showing a dominant phenotype (and whose genotype is to be determined) is crossed with the recessive parent instead of self-crossing. The progenies of such a cross can easily be analysed to predict the genotype of the test organism.

Topic: Biology, Principles of Inheritance and Variation, NEET
A wind with speed 40 m s-1 blows parallel to the roof of a house. The area of the roof is 250 m2 . Assuming that the pressure inside the house is atmospheric pressure, the force exerted by the wind on the roof and the direction of the direction of the force will be : ρair =1.2 kg m-3

Options:
A 4.8×105 N, downwards
B 4.8×105 N, upwards
C 2.4×105 N, upwards
D 2.4×105 N, downwards

The correct answer is:
2.4×105 N, upwards

Solution:
By Bernoulli's equation,
P+12ρv2=P0+0
P0-P=12ρv2
F=12ρv2A
=12×1.2×402×250
=12×1.2×1600×250
=2.4×105 N, upwards

Topic: Physics, Mechanical Properties of Fluids, NEET, NEET 2015 (Phase 1)
A wind-powered generator converts wind energy into electric energy. Assume that the generator converts a fixed fraction of the wind energy intercepted by its blades into electrical energy. For wind speed v, the electrical power output will be proportional to

Options:
A v
B v2
C v3
D v4

The correct answer is:
v3

Solution:
Power=F→·v→=Fv
F=v dmdt=v d ρ×volumedt
= ρvd volumedt= ρv Av= ρAv2
∴Power P=ρAv3 or P∝v3

Topic: Physics, Work Power Energy, NEET
A wire bent in the form a right-angled triangle PQR, carries a current 1 A. It is placed in a region of a uniform magnetic field B= 0.2 T. If PR = 1 m, the net force on the wire is

Options:
A 1.73 N
B 3.46 N
C 2.732 N
D Zero

The correct answer is:
Zero

Solution:
F → =i[ ℓ → × B → ]
∀ ℓ → = Vector length
here F→ = 0, for closed loop

Topic: Physics, Magnetic Effects of Current, NEET
A wire carrying a current I along the positive x-axis has length L. It is kept in a magnetic field B→=2i^+3j^-4k^ T. The magnitude of the magnetic force acting on the wire is:

Options:
A 3IL
B 3IL
C 5IL
D 5IL

The correct answer is:
5IL

Solution:
The formula to calculate the magnetic force acting on the wire is given by

F→=IL→×B→ ...1

As the length of the wire is along positive x-axis, it can be written that

L→=Li^ ...2

Substitute the expressions of the required parameters into equation (2) to obtain the force.

F→=ILi^×2i^+3j^-4k^=3ILk^+4ILj^ ...3

Hence, the magnitude of the force can be written as

F=3IL2+4IL2= 5IL

Topic: Physics, Magnetic Effects of Current, NEET, NEET 2023 (All India)
A wire carrying current I has the shape as shown in adjoining figure. Linear parts of the wire are very long and parallel to X -axis while semicircular portion of radius R is lying in Y - Z plane. Magnetic field at point O is :

Options:
A B→=μ04πIR πi^+2k^
B B→=-μ04πIR πi^-2k^
C B→=-μ04πIR πi^+2k^
D B→=μ04πIR πi^-2k^

The correct answer is:
B→=-μ04πIR πi^+2k^

Solution:
B→c = B→1+B→2+B→3.
B1 = μ04πR sin⁡90+sinθ-k^
B1 = μ04πR -k^=B3
B due to segment 2
B2 = μ0 I4π×π(-i^)=-μ0I4Ri^
So B at center B→c= B→1+ B→2+B→3
Bc= -μ0I4R i+2k^π= -μ0I4πR (π i^+2k^)

Topic: Physics, Magnetic Effects of Current, NEET, NEET 2015 (Phase 1)
A wire is 4 m long and has a mass 0.2 kg . The wire is kept horizontally. A transverse pulse is generated by plucking one end of the taut (tight) wire. The pulse makes four trips back and forth along the cord in 0.8 sec . The tension in the cord will be

Options:
A 80 N
B 160Â N
C 240Â N
D 320Â N

The correct answer is:
80 N

Solution:
4 trips means 32 m
Wave speed is,
v=dt=320.8=40 m s-1
v=TÎ¼
Therefore, tension in the cord is,
T=Î¼v2
T=0.24Ã402=2Ã16Ã104
T=80 N

Topic: Physics, Waves and Sound, NEET
A wire is bent to form a semicircle of radius a . The wire rotates about its one end with angular velocity ω . Axis of rotation being perpendicular to the plane of the semicircle. In the space, a uniform magnetic field of induction B exists along the axis of rotation, as shown in figure. Then

Options:
A potential difference between P and Q is equal to 2Bωa2
B potential difference between P and Q is equal to 2π2Bωa2
C P is at higher potential than Q
D none of these

The correct answer is:
potential difference between P and Q is equal to 2Bωa2

Solution:
e=12BÏl2
e=12BÏ2a2
e = 2BÏa2

Topic: Physics, Electromagnetic Induction, NEET
A wire is bent to form a semicircle of the radius a. The wire rotates about its one end with angular velocity ω. Axis of rotation is perpendicular to the plane of the semicircle. In the space, a uniform magnetic field of induction B exists along the axis of rotation as shown in the figure. Then -

Options:
A The potential difference between P and Q is equal to 2Bωa2
B potential difference between P and Q is equal to 2π2Bωa2
C P is at higher than Q
D None of these

The correct answer is:
The potential difference between P and Q is equal to 2Bωa2

Solution:
When wire of length l rotates with angular speed omega in external magnetic field then emf is induced in that wire.
e=12Bωl2=12Bω2a2=2Bωa2

Topic: Physics, Electromagnetic Induction, NEET
A wire is kept parallel to a square coil. Both carry current of the same amount. If the magnetic field due to the wire at any point P within the coil is B1, then the total magnetic field B at P will be

Options:
A B=0
B B>B1
C B<B1
D B=B1

The correct answer is:
B>B1

Solution:
As the field due to both- the straight wire and the coil are in the same direction, therefore net field at any point P within the coil is B>B1.

Topic: Physics, Magnetic Effects of Current, NEET
A wire is parallel to a square coil. The coil and wire carry currents in the directions shown. Then, at any point A within the coil the magnetic field will be-

Options:
A less than the magnetic field produced due to coil only
B more than the magnetic field produced due to coil only
C equal to the field by coil alone
D zero

The correct answer is:
more than the magnetic field produced due to coil only

Solution:
B due to wire is ⊗B due to loop is ⊗⇒Bnet=Bwire+Bcoil
⇒ Bnet is more than Bcoil .

Topic: Physics, Magnetic Effects of Current, NEET
A wire is wound on a long rod of the material of relative permeability Î¼ r = 4 0 0 0 to make a solenoid. If the current through the wire is 5 A and the number of turns per unit length is 1000 m-1, then the magnetic field inside the solenoid is :

Options:
A 25.12 mT
B 12.56 mT
C 12.56 T
D 25.12 T

The correct answer is:
25.12 T

Solution:
B = Î¼ 0 Î¼ r ni
= 1 0 - 7 Ã 4 Ï Ã 4 0 0 0 Ã 1 0 0 0 Ã 5
= 8 Ï T
= 25.12 T

Topic: Physics, Magnetic Effects of Current, NEET
A wire loop is rotated in a magnetic field. The frequency of change of direction of the induced emf is

Options:
A once per revolution
B wice per revolution
C four times per revolution
D six times per revolution

The correct answer is:
wice per revolution

Solution:
The knowledge based the correct choice is $(b)$.

Topic: Physics, Electromagnetic Induction, NEET, NEET 2013 (All India)
A wire loop that encloses an area of 20 cm2 has a resistance of 10 Î©. The loop is placed in a magnetic field of 2.4 T with its plane perpendicular to the field. The loop is suddenly removed from the field. How much charge flows past a given point in the wire?

Options:
A 12Ã10-4 C
B 3.6Ã10-1 C
C 4.8Ã10-4 C
D 2.4Ã10-3 C

The correct answer is:
4.8Ã10-4 C

Solution:
Given,
Resistance, R=10 Î©
Area of the loop, A=20 cm2=20Ã10-4 m2
Magnetic field, B=2.4 T
As we know, induced emf e=+dÏdt â IR=dÏdt
â dQdt.R=dÏdtââ«dQ=â«dÏR
â Q=ÏR [âµÏ=BA cos0o=BA]
=(20Ã10-4)(2.4)10
=4.8Ã10-4 C

Topic: Physics, Magnetic Effects of Current, NEET
A wire made of aluminium having resistivity Ï=2.8Ã10-8 Î©-m with a circular cross-section and has a radius of 2Ã10-3 m. A current of 5 A flows through the wire. If the voltage difference between the ends is 1 V, the length of the wire in m is

Options:
A 50
B 60
C 90
D 120

The correct answer is:
90

Solution:
Given, resistivity ρ=2.8×10-8Ω-m ,
Radius r=2×10-3 m,
Current I=5 A
Voltage difference V=1 V
∵ Resistivity ρ=RAl
∴ 2.8×10-8=Rπ2×10-32l
⇒ l=Rπ×4×10-62.8×10-8
⇒ l=VI4π×10-62.8×10-8 (from ohm's law ,V=IR)
l=15×4π×10-62.8×10-8=0.897×102=89.7 m
≈90 m

Topic: Physics, Current Electricity, NEET
A wire mesh consisting of very small squares is viewed at a distance of 8 cm through a magnifying converging lens of focal length 10 cm, kept close to the eye. The magnification produced by the lens is

Options:
A 5
B 8
C 10
D 20

The correct answer is:
5

Solution:
Lens formula is given by
1f=1v-1u …i
Where f is focal length of lens, v is image distance and u is object distance.
Given f=10 cm (as lens is converging)
u= -8 cm (as object is placed on left side of the lens)
Substituting these values in Eq. (i) , we get
110=1v-1-8
⇒1v=110-18
⇒1v=8-1080
∴v=80-2=-40 cm
Hence, magnification produced by the lens
m=vu=-40-8=5

Topic: Physics, Ray Optics, NEET
A wire of arbitrary shape carries a current I=2 A. Consider the portion of wire between (0,0,0) and (4,4,4). A magnetic filled given by Bâ=12Ã10-4i^+2Ã10-4j^ T exists in the region. The force acting on the given portion the wire is

Options:
A F→=i^+j^+k^×12i^+12j^ N
B Fâ=8Ã10-4i^+j^+k^Ã12i^+2j^ N
C Zero
D None of the above

The correct answer is:
Fâ=8Ã10-4i^+j^+k^Ã12i^+2j^ N

Solution:
The magnetic force in the uniform magnetic field is
F→=I(L→×B→)
L→=4i^+4j^+4k^ and
B→=(12i^+2j^)×10-4 T
∴F→=8×10-4[(i^+j^+k^)×(12i^+2j^)] N

Topic: Physics, Magnetic Effects of Current, NEET
A wire of length ' 1 and resistance $100 \Omega$ is divided into 10 equal parts. The first 5 parts are connected in series while the next 5 parts are connected in parallel. The two combinations are again connected in series. The resistance of this final combination is:

Options:
A $52 \Omega$
B $55 \Omega$
C $60 \Omega$
D $26 \Omega$

The correct answer is:
$52 \Omega$

Solution:
Divided into 10 parts
$\begin{aligned}
R & =\frac{\rho l}{A} \\
R^{\prime} & =\frac{\rho l}{10 A}=\frac{R}{10} \\
R_S & =5 \times \frac{R}{10} \quad \text { [series] } \\
R_S & =50 \\
R_P & =\frac{R}{50} \quad \text { [parallel] } \\
R_{\text {eq }} & =R_S+R_P \\
& =52 \Omega
\end{aligned}$

Topic: Physics, Current Electricity, NEET, NEET 2024
A wire of length 10 m is subjected to a force of 100 N along its length and hence the lateral strain produced is 0.01Ã10-3 m. The Poisson's ratio was found to be 0.4. If the area of cross-section of wire is 0.025 m2, its Young's modulus will be

Options:
A 1.6×108 Nm-2
B 2.5×1010 Nm-2
C 1.25×1011Nm-2
D 16×109Nm-2

The correct answer is:
1.6×108 Nm-2

Solution:
Poisson's ratio =Lateral strainLongitudinal strain
ie, 0.4=0.01×10-3lL
or Ll=0.40.01×10-3=4×104
Young's modulus
Y=FLAl
=1000.025×4×104=1.6×108Nm-2

Topic: Physics, Mechanical Properties of Solids, NEET
A wire of length 100 m is tightly wounded on a hollow tube of radius 5 mm and length 1 m. A current of 1 A is flowing in the wire. Then magnetic field strength inside the tube will be :-

Options:
A 4 T

B 4 mT

C 40 mT
D 40 T

The correct answer is:
4 mT

Solution:
Field due to a solenoid = μ 0 ni
Given i = 1 A
n = 1 0 0 2 π × 5 × 1 0 - 3
∴ B=μ0ni=4π×10-7×100×12π×5×10-3=4 mT

Topic: Physics, Magnetic Effects of Current, NEET
A wire of length L and radius r is clamped rigidly at one end. When the other end of the wire is pulled by a force f, its length increases by l. Another wire of the same material of length 2L and radius 2r, is pulled by a force 2f. Find the increase in length of this wire.

Options:
A l/2
B l
C 2l
D 4l

The correct answer is:
l

Solution:
Correct Option is : (B)
l

Topic: Chemistry, Mechanical Properties of Solids, NEET
A wire of length L, area of cross section A is hanging from a fixed support. The length of the wire changes to L1 when mass M is suspended from its free end. The expression for Young's modulus is:

Options:
A MgL1−LAL
B MgLAL1
C MgLAL1−L
D MgL1AL

The correct answer is:
MgLAL1−L

Solution:
We know that,

Young's modulus, Y=FLAΔL

Given,

F=Weight of suspended body=Mg and ∆L=L1-L.

So, we can write

Y=MgLAL1-L

Topic: Physics, Mechanical Properties of Solids, NEET, NEET 2020 (Phase 1)
A wire of length L metre carrying a current of I ampere is bent in the form of a circle. Its magnetic moment is,

Options:
A IL24 A m2
B πIL24 A m2
C 2IL2π A m2
D IL24π A m2

The correct answer is:
IL24π A m2

Solution:
When a wire of length, L bent in the form of a circle of radius, r then the relation between radius and length, by the formula of circumference, 2πr=L,

⇒r=L2π, for one number of turns, the formula for the magnetic moment is,

M=I(A)⇒M=Iπr2=I(π)L2π2=IL24π $\mathrm{Am}^{2}$

Topic: Physics, Magnetic Effects of Current, NEET, NEET 2020 (Phase 2)
A wire of natural length l, Young's modulus Y and area of cross-section A is extended by x. Then the energy stored in the wire is given by

Options:
A 12 YAlx2
B 13Â YAlx2
C 12Â YlAx2
D 12Â AYlx2

The correct answer is:
12 YAlx2

Solution:
Energy stored in the wire
U=12Y×(strain)2×volume
or U=12Y×xl2×Al
or U=12Yx2l×A
or U=12YAlx2

Topic: Physics, Mechanical Properties of Solids, NEET
A wire of resistance $4 \Omega$ is stretched to twice its original length. The resistance of stretched wire would be

Options:
A $2 \Omega$
B $4 \Omega$
C $8 \Omega$
D $16 \Omega$

The correct answer is:
$16 \Omega$

Solution:
Let length and cross-section area of the wire be l and A respectively.
\(\therefore\) Resistance \(\mathrm{R}=\rho \frac{\mathrm{l}}{\mathrm{A}}\) where \(\rho\) is the resistivity of the material
Given: \(R=4 \Omega\)
For \(l^{\prime}=2 l\) and \(A^{\prime}=\frac{A}{2}\), resistance of the wire be \(R^{\prime}\)
\(\begin{aligned}
& \therefore R^{\prime}=\rho \frac{l^{\prime}}{A^{\prime}}=\rho \frac{2 l}{A / 2}=4 \rho \frac{1}{A}=4 R \\
& \therefore R^{\prime}=4 \times 4 \Omega=16 \Omega
\end{aligned}\)

Topic: Physics, Current Electricity, NEET, NEET 2013 (All India)
A wire of resistance 0.5 Î© m-1 is bent into a circle of radius 1 m. The same wire is connected across a diameter AB as shown in the figure. The equivalent resistance is

Options:
A Ï Î©
B ππ+2 Ω
C ππ+4 Ω
D (π+1) Ω

The correct answer is:
ππ+4 Ω

Solution:
Rl=0.5 Ω m-1, r=1 m
Length of semicircle =πr
Hence the resistance of semicircle
R=0.5×πr
R=12×π×1
R=π2 Ω
Resistance of diameter
R=0.5×2r
R=0.5×2×1
R=1
1Req=1R1+1R2+1R3
1Req=2π+11+2π
1Req=4π+1
Req=ππ+4

Topic: Physics, Current Electricity, NEET
A wire of resistance $12 \Omega \mathrm{m}^{-1}$ is bent to form a complete circle of radius $10 \mathrm{~cm}$. The resistance between its two diametrically opposite points, $A$ and $B$ as shown in the figure, is

Options:
A $0.6 \pi \Omega$
B $3 \Omega$
C $6 \pi \Omega$
D $6 \Omega$

The correct answer is:
$0.6 \pi \Omega$

Solution:
.
Circumference of circle $=2 \times \pi \frac{10}{100}=\frac{2 \pi}{10}=\frac{\pi}{5}$
Resistance of wire $=12 \times \frac{\pi}{5}=\frac{12 \pi}{5}$
Resistance of each section $=\frac{12 \pi}{10} \Omega$
$\therefore$ Equivalent resistance
$$
=\frac{\frac{12 \pi}{10} \times \frac{12 \pi}{10}}{\frac{12 \pi}{10}+\frac{12 \pi}{10}}=\frac{6 \pi}{10}=0.6 \pi \Omega
$$

Topic: Physics, Current Electricity, NEET, NEET 2009 (Screening)
A wire of resistance 18 Ω is divided into three equal parts. These parts are connected as sides of a triangle, the equivalent resistance of any two corners of the triangle will be

Options:
A 18 Î©
B 9 Î©
C 6 Î©
D 4 Î©

The correct answer is:
4 Î©

Solution:
To find equivalent resistance across
BC, AB and AC is in series
Râ²=6+6=12 Î©
12 Î© and 6 Î© is in parallel
Total resistance,
R=12Ã612+6
R=7218=4 Î©

Topic: Physics, Current Electricity, NEET
A woman accidentally touched a hot pan without wearing a pair of mittens. On contact, she immediately yanks her hand away.
Select the CORRECT statement with respect to the above phenomenon.

Options:
A The signal received from the sensory organ is carried into the PNS.
B The efferent neuron receives the signal from the sensory organ.
C The impulse is transported via a dorsal nerve root to the spinal cord.
D The action is voluntary in nature which involves conscious effort and thought.

The correct answer is:
The impulse is transported via a dorsal nerve root to the spinal cord.

Solution:
When a person comes in contact with an extremely hot object, he or she quickly remove themselves away from it. The entire process of response to a peripheral nervous stimulation, that occurs involuntarily, i.e., without conscious effort or thought and requires the involvment of a part of the central nervous system is called a reflex action. The reflex pathway comprises at least one afferent neuron (receptor) and one efferent (effector or excitor) neuron appropriately arranged in a series. The afferent neuron receives signal from a sensory organ and transmits the impulse via a dorsal nerve root into the CNS (at the level of spinal cord). The efferent nueuron then carries signals from CNS to the effector.

Topic: Biology, Neural Control and Coordination, NEET
A woman had an extreme premature delivery. She gave birth to a baby boy at 23 weeks of gestation. The birth weight of the baby was 950 gm . Which of the following is most likely to be observed in this baby?

Options:
A The baby's heart will not be adequately formed
B The baby's limbs and digits will not be adequately formed
C The baby's external genitalia will not be adequately formed
D The baby's eyelashes will not be adequately formed

The correct answer is:
The baby's eyelashes will not be adequately formed

Solution:
The baby's heart forms after 4 weeks of pregnancy. The limbs and digits form at the end of 8 weeks. The external genitals form at the end of 12 weeks. As the baby was born at 23 weeks, these features will mostly be well developed in the baby. Features like body hair, separation of eyelids and formation of eyelashes complete at the end of 24 weeks. As the baby was born prior to it, most likely these features will not be adequately formed in the baby.

Topic: Biology, Human Reproduction, NEET
A woman has a haemophilic son and three normal children. Her genotype and that of her husband with respect to this gene would be

Options:
A XXÂ andÂ XhY
B XhXhÂ andÂ XhY
C XhXhÂ andÂ XY
D XhX and XY

The correct answer is:
XhX and XY

Solution:
Because no other child is affected or is a carrier, it is more likely that man is normal and women is heterozygous. If the father is affected, all daughters will be carriers and if the mother is affected, all daughter will be carriers and sons will be affected.

Topic: Biology, Principles of Inheritance and Variation, NEET
A woman has X-linked condition on one of her X chromosomes. These chromosomes can be inherited by:

Options:
A Only grandchildren
B Only sons
C Only daughters
D Both sons and daughters

The correct answer is:
Both sons and daughters

Solution:
The woman is the carrier of X-linked condition, and she can transmit the carrier allele to both her son and daughter, The resulting son will become diseased because X-linked disorder always affect males due to the presence of single X-chromosome.

The daughter offspring will become a carrier but not diseased because females are affected by X-linked disorder in homozygous recessive condition, i.e. two recessive alleles are required.

Topic: Biology, Principles of Inheritance and Variation, NEET, NEET 2018
A woman is having an abnormal menstrual cycle due to improper regulation of the thyroid gland. Calculate the day of ovulation in such a female if her menstrual cycle duration is about 36 days.

Options:
A 19th day
B 14th day
C 16th day
D 22nd day

The correct answer is:
22nd day

Solution:
Day of ovulation is calculated by subtracting 14 days from the total duration of the menstrual cycle because the secretory phase is the most constant phase of the menstrual cycle (= 14 days).
In this case day of ovulation = 36 - 14 = 22.

Topic: Biology, Human Reproduction, NEET
A woman throws an object of mass 500 g with a speed of 25 m/s. What is the impulse imparted to the object?

Options:
A 12.5 N s
B 125 N s
C 250 N s
D 25 N s

The correct answer is:
12.5 N s

Solution:
Correct Option is : (A)
12.5 N s

Topic: Chemistry, Laws of Motion, NEET
A woman (whose father is colour blind but mother is normal) marries a haemophiliac man with hypertrichosis. What percentage of progeny will show genotypically any two of the traits out of the three mentioned above at a given time?

Options:
A 0 %
B 25 %
C 50 %
D 75 %

The correct answer is:
50 %

Solution:
Let Xc be the X chromosome with colourblindness gene, Xh be the X chromosome with haemophilia gene and Yt be the Y chromosome with hypertrichosis gene.
The woman receives on X chromosome from colourblind father and one X chromosome from a normal mother. Her genotype will be XXc. The man is heamophilic with hypertrichosis, so his genotype will be XhYt.
Their possible progenies will be

Xh	Yt
X	XXh	XYt
Xc	XcXh	XcYt

Genotypically any two of the traits out of the three traits will be seen in XcXh and XcYt. Thus the answer is 50%

Topic: Biology, Principles of Inheritance and Variation, NEET
A woman whose mother is colourblind and father is haemophilic marries a man whose mother is haemophilic and father is colourblind. Which of the following is correct about its progeny?

Options:
A They won't have any child who is free from both these diseases.
B Half of their children are haemophilic while the other half are colourblind.
C Half of their children will be colourblind while one fourth will be hameophilic
D Half of their children will be haemophilic while one fourth will be colourblind

The correct answer is:
Half of their children will be haemophilic while one fourth will be colourblind

Solution:
Xh = X chromosome carrying colourblindness gene. Xh = X chromosome carrying the haemophilia gene.
Mother of the woman is colourblind, hence her genotype will be XcXc. Father of the woman is haemophilic, hence his genotype will be XhY. The woman receives one X chromosome from her father (it has to be Xh) and the other X chromosome from her mother (it has to be Xc). Thus the genotype of the woman is Xc Xh(She is a carrier for colourblindness as well as haemophilia)
Mother of the man is haemophilic, hence her genotype will be XhXh. Father of the man is colourblind, hence his genotype will be XcY. The man receives Y chromosome from his father and X chromosome from his mother (it has to be Xh). Thus the genotype of the man is XhY.
The genotypes of their children can be represented as follows

Xc	Xh

Xh	XcXh daughter: carrier for both diseases	XhXh daughter: haemophilic

Y	XcY son: colourblind	XhY son: haemophilic

Topic: Biology, Principles of Inheritance and Variation, NEET