datavorous/entrance-exam-dataset huggingface dataset:
The wire of potentiometer is made of

Options:
A copper
B steel
C manganin
D aluminium

The correct answer is:
manganin

Solution:
Manganin is used in potentiometer as its temperature coefficient of resistance is virtually zero and it has long term stability.

Topic: Physics, Current Electricity, NEET
The word systematics is derived from the Latin word 'systema' which means?

Options:
A Greek, evolutionary classification
B Latin, systematic arrangement of organisms
C English,taxonomy of organisms

D Both (A) and (C)

The correct answer is:
Latin, systematic arrangement of organisms

Solution:
The word systematics is derived from the Latin word 'systema' which means the systematic arrangement of organisms. Linnaeus used Systema Naturae as the title of his publication.

Topic: Biology, The Living World, NEET
The work done by all the forces (external and internal) on a system is equal to the change in

Options:
A total energy
B kinetic energy
C potential energy
D none of these

The correct answer is:
kinetic energy

Solution:
According to Work Energy Theorem work done by all forces is equal to change in kinetic energy.

Topic: Physics, Work Power Energy, NEET
The work done during expansion of a gas from a volume of $4 \mathrm{dm}^3$ to $6 \mathrm{dm}^3$ against a constant external pressure of $3 \mathrm{~atm}$ is $(1 \mathrm{~L} \mathrm{~atm}=101.32 \mathrm{~J})$ :

Options:
A $-6 \mathrm{~J}$
B $-608 \mathrm{~J}$
C $+304 \mathrm{~J}$
D $-304 \mathrm{~J}$

The correct answer is:
$-608 \mathrm{~J}$

Solution:
Work $=-P_{e x t} \times$ volume change
$$
\begin{aligned}
& =3 \times 101.32 \times(6-4) \\
& =6 \times 101.32 \\
& =-607.92 \mathrm{~J}=-608 \mathrm{~J}
\end{aligned}
$$

Topic: Chemistry, Thermodynamics (C), NEET, NEET 2004
The work done during reversible isothermal expansion of one mole of hydrogen gas at $25^{\circ} \mathrm{C}$ from pressure of 20 atmosphere to 10 atmosphere is
(Given $\mathrm{R}=2.0 \mathrm{cal} \mathrm{K}^{-1} \mathrm{~mol}^{-1}$ )

Options:
A -413.14 calories
B 413.14 calories
C 100 calories
D 0 calorie

The correct answer is:
-413.14 calories

Solution:
$\begin{aligned} W_{\text {rev, iso }} & =-2.303 n R T \log \frac{P_i}{P_f} \\ & =-2.303 \times 1 \times 2 \times 298 \times \log 2 \\ & =-2.303 \times 1 \times 2 \times 298 \times 0.3 \\ & =-413.14 \text { calories }\end{aligned}$

Topic: Chemistry, Thermodynamics (C), NEET, NEET 2024
The work done in blowing a soap bubble of 10 cm radius is ( surface tension of the soap solution is 3100 N m-1â )

Options:
A 75.36×10-4 J⁡
B 37.68×10-4 J⁡
C 150.72×10-4 J⁡
D 75.36 J⁡

The correct answer is:
75.36×10-4 J⁡

Solution:
W⁡=8πR⁡2T⁡=8π10×10-223100=75.36×10-4 J

Topic: Physics, Mechanical Properties of Fluids, NEET
The work done in moving a particle in the gravitational field of earth from point A to point B along three different paths 1, 2 and 3 are W1, W2 and W3 respectively, then

Options:
A W1>W2>W3
B W1=W2=W3
C W1<W2<W3
D W2>W1>W3

The correct answer is:
W1=W2=W3

Solution:
The gravitational field of a point mass 'm' is a conservative field, in which the work done in moving a particle from one point to another depends upon the initial and final positions of the particle and not on the actual path travelled by the particle. Hence the work done along all the three paths 1, 2 and 3 is the same. i.e. W1=W2=W3 .

Topic: Physics, Gravitation, NEET
The work done in rotating a magnet of the magnetic moment 2 A m2 in a magnetic field of induction 5Ã10â3 T from the direction along the magnetic field to the direction opposite to the field, is

Options:
A Zero
B 2×10–2 J
C 10–2 J
D 10 J

The correct answer is:
2×10–2 J

Solution:
W=MB(1-cosθ); where θ=180°
⇒W=2MB⇒W=2×2×5×10-3=2×10-2 J

Topic: Physics, Magnetic Effects of Current, NEET
The work done to get n smaller equal size spherical drops from a bigger size spherical drop of water is proportional to

Options:
A 1n23-1
B 1n13-1
C n13-1
D n43-1

The correct answer is:
n13-1

Solution:
43ÏR3=nÃ43Ïr3 or r=Rn13
Now work done = increase in area Ã surface tension
W=4Ïr2n-4ÏR2ÃT
W=4ÏR2n23n-R2ÃT
Wân13-1

Topic: Physics, Mechanical Properties of Fluids, NEET
The work done to raise a mass m from the surface of the earth to a height h, which is equal to the radius of the earth is:

Options:
A mgR
B 2mgR
C 12mgR
D 32mgR

The correct answer is:
12mgR

Solution:
W=Uf-Ui
=-GMm2R--GMmR
=GMm2R
W=12mgR ∵ GMR2=g

Topic: Physics, Gravitation, NEET, NEET 2019 (All India)
The work function for caesium atom is 1.9 eV. Calculate (i) the threshold wavelength and (ii) the threshold frequency of the radiation

Options:
A (i) 786.32 nm and (ii) 4.598×1014s–1
B (i) 652.46 nm and (ii) 4.598×1014s–1
C (i) 652.46 nm and (ii) 6.523×1014s–1
D (i) 786.32 nm and (ii) 6.523×1014s–1

The correct answer is:
(i) 652.46 nm and (ii) 4.598×1014s–1

Solution:
Correct Option is : (B)
(i) 652.46 nm and (ii) 4.598×1014s–1

Topic: Chemistry, Structure of Atom, NEET
The work function for caesium atom is 1.9 eV. If the caesium element is irradiated with a wavelength 500 nm, calculate (i) the kinetic energy and (ii) the velocity of the ejected photoelectron.

Options:
A (i)9.29 ×10–20J and (ii) 7.265 × 105ms–1
B (i)6.36 ×10–20J and (ii) 4.516 × 105ms–1
C (i)9.29 ×10–20J and (ii) 4.516 × 105ms–1
D (i)8.36 ×10–20J and (ii) 7.265 × 105ms–1

The correct answer is:
(i)9.29 ×10–20J and (ii) 4.516 × 105ms–1

Solution:
Correct Option is : (C)
(i)9.29 ×10–20J and (ii) 4.516 × 105ms–1

Topic: Chemistry, Structure of Atom, NEET
The work function of a metal is 1 eV. Light of wavelength 3000 Aâ is incident on this metal surface. The velocity of emitted photoelectrons will be

Options:
A 10 m s-1
B 103 m s-1
C 104 m s-1
D 106 m s-1

The correct answer is:
106 m s-1

Solution:
12mv2=hcÎ»-Ï0
=6.63Ã10-34Ã3Ã108(3Ã10-7)Ã1.6Ã10-19-1
=4.14-1=3.14 eV
or v=2Ã3.14Ã1.6Ã10-199.1Ã10-31=106 m s-1

Topic: Physics, Dual Nature of Matter, NEET
The work function of a metal is in the range of 2âeVââtoââ5 eV. Find which of the following wavelength of light cannot be used for the photoelectric effect. (Consider, Planck's constant =4Ã10â15 eV s, the velocity of light =3Ã108âm s-1)

Options:
A 510 nm
B 650 nm
C 400 nm
D 570 nm

The correct answer is:
650 nm

Solution:
Given that, 2 eV ≤ϕ≤5 eV
Wavelength corresponding to the minimum and maximum values of work function are
λmax=hcE=4×10-15×3×1082
= 6×10-7m=600 nm
And λmin=hcE=4×10-15×3×1085
= 2.4×10-7m=240 nm
Clearly wavelength range would be 240≤λ≤600
Thus, the wavelength 650 nm is not suitable for the photoelectric effect.

Topic: Physics, Dual Nature of Matter, NEET
The work function of a metal surface is 4 eV. The longest wavelength of light that can cause photoelectron emission from this surface is approximately

Options:
A 540 nm
B 400 nm
C 310 nm
D 220 nm

The correct answer is:
310 nm

Solution:
Let Î»m = Longest wavelength of light

hâ¡ câ¡ Î» mâ¡ = Ï work function

Therefore, Î» m = hc Ï = (6.63 Ã 10 -34 ) 3 Ã 10 8 4.0 Ã 1.6 Ã 10 - 1 9

Or Î»m = 310 nm.

Topic: Physics, Dual Nature of Matter, NEET
The work function of a photosensitive material is $4.0 \mathrm{eV}$. This longest wavelength of light that can cause photon emission from the substance is (approximately)

Options:
A $3100 \mathrm{~nm}$
B $966 \mathrm{~nm}$
C $31 \mathrm{~nm}$
D $310 \mathrm{~nm}$

The correct answer is:
$310 \mathrm{~nm}$

Solution:
The work function of material is given by
$$
\begin{aligned}
& \phi=\mathrm{hv} \\
& \phi=\frac{\mathrm{hc}}{\lambda}
\end{aligned}
$$
$$
\text { ..(i) }\left[\because v=\frac{c}{\lambda}\right]
$$
where, $\mathrm{h}=$ Planck's constant $=6.63 \times 10^{-34} \mathrm{~J}-\mathrm{s}$
$\mathrm{c}=$ speed of length $=3 \times 10^8 \mathrm{~ms}^{-1}$ and
$\lambda=$ wavelength of light
Here, $\phi=4 \mathrm{eV}=4 \times 1.6 \times 10^{-19} \mathrm{~J}$
Substituting the given values in Eq. (i), we get $\Rightarrow \quad 4 \times 1.6 \times 10^{-19}=\frac{6.63 \times 10^{-34} \times 3 \times 10^8}{\lambda}$
or $\quad \lambda=\frac{6.63 \times 10^{-34} \times 3 \times 10^8}{4 \times 1.6 \times 10^{-19}}$
$=3.108 \times 10^{-7} \mathrm{~m} \simeq 310 \mathrm{~nm}$

Topic: Physics, Dual Nature of Matter, NEET, NEET 2019 (Odisha)
The work function of a substance is 4.0 eV. The longest wavelength of light that can cause photoelectron emission from this substance is approximately

Options:
A 540 nm
B 400 nm
C 310 nm
D 220 nm

The correct answer is:
310 nm

Solution:
The maximum wavelength which is responsible for emission of photoelectron is
Î»0=hcW0=12404
= 310 nm

Topic: Physics, Dual Nature of Matter, NEET
The work function of a surface of a photosensitive material is 6.2 eV. The wavelength of incident radiation for which the stopping potential is 5 V lies in the

Options:
A ultraviolet region
B visible region
C infrared region
D x - rays region

The correct answer is:
ultraviolet region

Solution:
Work function, ϕ0=6.2 eV
Stopping potential V0=5V
As eV0=hv-ϕ0
or eV0+ϕ0=hcλ
or λ=hceV0+ϕ0
λ=6.62×10-34 J s×3×108 m s-11.6×10-19×5 J+6.2×1.6×10-19 J
=6.62×10-34×3×1081.6×10-19(5+6.2) m
=19.86×10-2617.92×10-19=1.10×10-7 m.
Thus the wavelength of the incident radiation lies in the ultraviolet region.

Topic: Physics, Dual Nature of Matter, NEET
The work function of a surface of a photosensitive material is $6.2 \mathrm{eV}$. The wavelength of the incident radiation for which the stopping potential is $5 \mathrm{~V}$ lies in the

Options:
A ultraviolet region
B visible region
C infrared region
D X-ray region

The correct answer is:
ultraviolet region

Solution:
According to laws of photoelectric effect
$\mathrm{KE}_{\max }=E-\phi$
where $\phi$ is work function and $\mathrm{KE}_{\max }$ is maximum kinetic energy of photoelectron.
$\begin{array}{l}
\therefore h v=e V_0+\phi \\
\text {or } h v=5 \mathrm{eV}+6.2 \mathrm{eV}=11.2 \mathrm{eV} \\
\therefore \lambda=\left(\frac{12400}{11.2}\right) Å \approx 1000 Å
\end{array}$
Hence, the radiation lies in ultraviolet region.

Topic: Physics, Dual Nature of Matter, NEET, NEET 2008 (Screening)
The work function (ϕ) of some metals is listed below. The number of metals which will show photoelectric effect when light of 300 nm wavelength falls on the metals is :

Options:
A 2
B 4
C 6
D 8

The correct answer is:
4

Solution:
Energy of photon=hcÎ»J=hceÎ»eV
=6.625Ã10-34Ã3Ã108300Ã10-9Ã1.602Ã10-19=4.14 eV
For photoelectric effect to occur, energy of incident photons, must be greater than work functions of metal. Hence, only Li, Na, K and Mg have work functions less than 4.14 V.

Topic: Chemistry, Structure of Atom, NEET
The work function of the metal A is equal to the ionization energy of the hydrogen atom in the first excited state. The work function of the metal B is equal to the ionization energy of He+ ion in the second orbit. Photons of the same energy E are incident on both A and B. The maximum kinetic energy of photoelectrons emitted from A is twice that of photoelectrons emitted from B. Value of E ( in eV) is

Options:
A 23.8 eV
B 20.8 eV
C 32.2 eV
D 24.6 eV

The correct answer is:
23.8 eV

Solution:
En=13.6Z2n2
WA= ionization energy of an electron in 2nd orbit of the hydrogen atom = 3.4 eV
WB = ionization energy of an electron in 2nd orbit of He+ ion
= 13.6 eV.
Now, given that
KA=2KB
or E-WA=2E-WB
∴ E=2WB-WA=23.8 eV

Topic: Physics, Dual Nature of Matter, NEET
The work functions for metal $\mathrm{a}, \mathrm{b}$ and c are respectively $1.92 \mathrm{eV}, 2.0 \mathrm{eV}$ and 5 eV. According to Einstein's equation the metals which will emit photoelectrons for a radiation of wavelength $4100 Å$ is a/are:

Options:
A none
B 'a' only
C 'a' and 'b' only
D all the three metals

The correct answer is:
'a' and 'b' only

Solution:
Energy of photon $=\frac{12400}{4100}=3 \mathrm{eV}$

Topic: Physics, Dual Nature of Matter, NEET, NEET 2005
The work functions of Caesium (Cs), Potassium(K) and Sodium (Na) 2.14 eV, 2.30 eV and 2.75 eV are respectively. If incident electromagnetic radiation has an incident energy of 2.20 eV, which of these photosensitive surfaces may emit photoelectrons?

Options:
A Na only
B Cs only
C Both Na and K
D K only

The correct answer is:
Cs only

Solution:
For emission of photoelectrons, incident photon energy should be more than the work function of the metal.

Given:

hν= 2.20 eV.

Clearly,

hν>ϕCs but hν<ϕK and hν<ϕNa.

Therefore, only Cs will emit photoelectrons.

Topic: Physics, Dual Nature of Matter, NEET, NEET 2023 (All India)
The work functions of three metals A, B and C are WA, WB and WC respectively. They are in decreasing order. The correct graph between kinetic energy and frequency Î½ of incident radiation is

Options:
A
B
C
D

The correct answer is:

Solution:
Irrespective of the photosensitive material used, the slope of each line should be same, since slope =he
Since, WA>WB>WC â Î½0A>Î½0B>Î½0C.
â´ a is not possible.
Options (iii) and (iv) are not possible, since the graphs are not parallel.

Topic: Physics, Dual Nature of Matter, NEET
The work of 146 kJ is performed in order to compress one kilomole of a gas adiabatically and in this process the temperature of the gas increase by 7 Â°C. The gas is R=8.3J mol-1K-1

Options:
A Diatomic
B Triatomic
C A mixture of monoatomic and diatomic
D None of the above

The correct answer is:
Diatomic

Solution:
For the adiabatic process,
dQ=0
⇒ dU=-∆W
Or nCvdT=+146×103 J
⇒ nfR2×7=146×103 J
Where, f is the degree of freedom
⇒ 103×f×8.3×72=146×103 J
f=5.02 ≃5
Therefore, gas is diatomic.

Topic: Physics, Thermodynamics, NEET
The work required to put the four charges from infinity to the position shown here is

Options:
A -0.65q2πε0a
B -1.0q2πε0a
C 1-122q2ÏÎµ0a
D zero

The correct answer is:
-0.65q2πε0a

Solution:
Work is equal to the potential energy of the system.
U=4kq-qa+2kqqa2
U=kq2a-4+2
U=q2πε0a-1+24=-0.65q2πε0a

Topic: Physics, Electrostatics, NEET
The work that must be done in lifting a body of weight P from the surface of the earth to a height h is

Options:
A PRhR-h
B R+hPRh
C PRhR+h
D R-hPRh

The correct answer is:
PRhR+h

Solution:
Force on the body =GMmx2
To move it by a small distance dx,
Work done =F dx=GMmx2dx
Total work done =GMm â«RR+hdxx2=-GMmxRR+h
=GMm1R-1R+h
=R+h-RR(R+h)=GMmhR(R+h)
GMR2ÃmhRR+h=gmhRR+h=PRhR+h

Topic: Physics, Gravitation, NEET
The work-energy theorem states that the change in

Options:
A Kinetic energy of a particle is equal to the work done on it by the net force
B Kinetic energy of a particle is equal to the work done by one of the forces acting on it
C Potential energy of a particle is equal to the work done on it by the net force
D Total energy of a particle is equal to the work done on it by the net force

The correct answer is:
Kinetic energy of a particle is equal to the work done on it by the net force

Solution:
According to work-energy theorem, change in kinetic energy of a particle is equal to the work done on it by the net force., i.e.
W=F⋅S=12mv2

Topic: Physics, Work Power Energy, NEET
The World Summit is related to:

Options:
A Convention on Biological Diversity - Rio de Janerio, 1992
B Convention on Biological Diversity - Johannesburg, 1992
C Sustainable development - Rio de Janerio, 2002
D Sustainable development - Johannesburg, 2002

The correct answer is:
Sustainable development - Johannesburg, 2002

Solution:
Conservation of Biodiversity is the collective responsibility of all nations. The historic Convention on Biological Diversity ('The Earth Summit') held in Rio de Janeiro in 1992, called upon all nations to take appropriate measures for conservation of biodiversity and sustainable utilisation of its benefits. In a follow-up, the World Summit on Sustainable development held in 2002 in Johannesburg, South Africa, 190 countries pledged their commitment to achieve by 2010, a significant reduction in the current rate of biodiversity loss at global, regional and local levels.

Topic: Biology, Biodiversity and its Conservation, NEET
The World Summit on sustainable development held in 2002 in Johannesburg, South Africa pledged for:

Options:
A A significant reduction in the current rate of biodiversity loss.
B Declaration of more biodiversity hotspots.
C Increase in agricultural production
D Collection and preservation of seeds of different genetic strains of commercially important plants.

The correct answer is:
A significant reduction in the current rate of biodiversity loss.

Solution:
World summit on sustainable development takes place to ensure significant reduction in the current rate of Biodiversity loss. This summit was held in 2002 in Johannerburg, South Africa.

Topic: Biology, Biodiversity and its Conservation, NEET, NEET 2022 (Phase 2)
The world's highly prized wool yielding 'Pashmina' breed is:

Options:
A goat
B sheep
C goat-sheep cross
D Kashmir sheep-Afghan sheep cross.

The correct answer is:
goat

Solution:
The Himalayan Mountain goat, Capra hircus indigenous to high altitudes of the Himalayan mountains.
Related Theory
The Himalayan Mountain goat, Capra hircus indigenous to high altitudes of the Himalayan mountains.

Topic: Biology, Strategies for Enhancement in Food Production, NEET, NEET 2005
The worst environmental hazards were created by accidents in nuclear power plant and MIC gas tragedy, respectively in

Options:
A Russia in 1990 & Bhopal 1986
B Ukraine in 1988 & USA in 1984
C Bhopal in 1984 & Russia in 1990
D Ukraine in 1986 and Bhopal in 1984

The correct answer is:
Ukraine in 1986 and Bhopal in 1984

Solution:
The MIC gas tragedy occurred in Bhopal in 1984 and the Chernobyl tragedy (nuclear power plant) occurred in Ukraine in 1986.

Topic: Biology, Environmental Issues, NEET
The wrong statement about fertilization/ post fertilization changes in humans is

Options:
A Fertilisation can occur only if sperm and ovum simultaneously reach the ampulla of the fallopian tube.
B During fertilisation, the sperm comes in contact with the cell membrane of the ovum first.
C The division of the morula leads to the formation of blastocyst.
D The embryo is formed by the differentiation of inner cell mass.

The correct answer is:
During fertilisation, the sperm comes in contact with the cell membrane of the ovum first.

Solution:
During fertilisation, the sperm first comes in contact with the 'zona pellucida' layer of the ovum. Certain enzymes are released by the acrosome of the sperm. These enzymes cause certain changes in the zona pellucida layer. Thus, the entry of further sperms is prevented.

Topic: Biology, Human Reproduction, NEET
The x and y coordinates of a particle at any time t are given by x= 2t+4t2 and y= 5t , where x and y are in metre and t in second. The acceleration of the particle at t= 5 s is -

Options:
A 40 m s-2
B 20 m s-2
C 8 m s-2
D Zero

The correct answer is:
8 m s-2

Solution:
Considering the motion of particle in x and y direction.
vx=dxdt=2+8t
And ax=dvxdt=8
vy=dydt=5
And ay=dvydt=0
a=ax2+ay2
a=82+0= 8 m s-2

Topic: Physics, Motion In Two Dimensions, NEET
The x and y coordinates of a particle at any time t are given by x=2t+4t2 and y=5t, where x and y are in metre and t in second. The acceleration of the particle at t=5 s is

Options:
A 40 m s-2
B 20 m s-2
C 8 m s-2
D zero

The correct answer is:
8 m s-2

Solution:
For x component
vx=dxdt=2+8t m s-1
ax=dvxdt=8 m s-2
For y component
vy=dydt=5 m s-1
ay=dvydt=0

Topic: Physics, Motion In Two Dimensions, NEET
The x and y coordinates of a particle at any time t are given by x=7t+4t2 and y=5t. where x and y are in metre and t in second. The acceleration of the particle at t=5 s is

Options:
A zero
B 8 m s-2
C 20 m s-2
D 40 m s-2

The correct answer is:
8 m s-2

Solution:
a=ax2+ay2
= d 2 x dt 2 2 + d 2 y dt 2 2 1 2

ax=d2xdt2=8

ay=d2ydt2=0
Hence, a=d2xdt2=8 m s-2

Topic: Physics, Motion In One Dimension, NEET
The x and y coordinates of the particle at any time are x=5t-2t2 and y=10t respectively, where x and y are in meters and t is in seconds. The acceleration of the particle at t=2 s is

Options:
A 0 m s-2
B 5 m s-2
C -4 m s-2
D -8 m s-2

The correct answer is:
-4 m s-2

Solution:
x=5t-2t2 y =10t
dxdt=5-4t dydt=10
The velocity of the particle in x and y coordinate is

vx=5-4t vy =10
dvxdt=-4 dvydt=10

ax= -4 ay=0
Acceleration of particle at t=2 s is =-4 m/s2

Topic: Physics, Motion In One Dimension, NEET, NEET 2017
The ________X________ cells of testes secrete testosterone in ___________.

Choose the correct option for X and Y.

Options:
A X: Leydig ; Y: Seminiferous tubules
B X: Sertoli cells ; Y: Blood
C X: Sertoli cells; Y: Seminiferous tubules
D X: Leydig ; Y: Blood

The correct answer is:
X: Leydig ; Y: Blood

Solution:
The regions outside the seminiferous tubules interstitial spaces, which all interstitial spaces which contain interstitial cells or Leydig cells, which synthesise and secrete testicular hormones also called androgens in blood.

Topic: Biology, Human Reproduction, NEET
The ________X__________ cells of testes, which are present inside the seminiferous tubule of testes synthesize and secretes ________Y________ hormones.

Choose the correct option for X and Y.

Options:
A X: Leydig ; Y: Androgens
B X: Interstitial ; Y: Testicular
C X: Sertoli ; Y: Inhibin B
D Both (a) and (b)

The correct answer is:
X: Sertoli ; Y: Inhibin B

Solution:
The regions outside the seminiferous tubules called interstitial spaces, which contain interstitial cells or Leydig cells, which synthesize and secretes testicular hormones also called androgens.
The region inside the seminiferous tubules contains Sertoli or nurse cells, which secrete the hormone inhibin B.

Topic: Biology, Human Reproduction, NEET
The x-t graph of a particle performing simple harmonic motion is shown in the figure. The acceleration of the particle at t=2 s is:

Options:
A -π216 m s-2
B π28 m s-2
C -π28 m s-2
D π216 m s-2

The correct answer is:
-π216 m s-2

Solution:
From the figure, it can be concluded that

A=1ω=2π8=π4

Hence, the equation of motion of the particle is given by

x=Asinωt=sinπ4t ...1

The velocity of the particle is, then, given by

v=dxdt=ddtsinπ4t= π4cosπ4t ...2

Hence, the acceleration of the particle can be written as

a=dvdt=ddtπ4cosπ4t=-π216sinπ4t ...3

Substitute 2 for t into equation (3) to calculate the required value of the acceleration.

a=-π216sinπ4×2= -π216 ms-2

Topic: Physics, Oscillations, NEET, NEET 2023 (All India)
The x - t graph of a particle undergoing simple harmonic motion is shown below. The acceleration of the particle at t=43 s is

Options:
A 332 Ï2 cm s-2
B -Ï232Â cm s-2
C Ï232Â cm s-2
D -332 Ï2 cm s-2

The correct answer is:
-332 Ï2 cm s-2

Solution:
From the graph Time period of wave T=8 s. and Amplitude A=1 cm
ω= 2π T = π 4rad s-1
and x=Asinωt=sinπ4t
acceleration at any time t is
a=-ω​2x=-π42⁡sinπ4t
Substituting t=43 s, we get
a= -332π2 cm s-2

Topic: Physics, Oscillations, NEET
The xenon compound that are isostructural with IBr2Θ and BrO3Θ respectively are -

Options:
A Linear XeF2 and pyramidal SO3
B Bent XeF2 and pyramidal XeO3
C Bent XeF2 and planar XeO3
D Linear XeF2 and pyramidal XeO3

The correct answer is:
Linear XeF2 and pyramidal XeO3

Solution:
XeF2 is isostructural with IBr2Θ both are linear
and XeO3 is isostructural with IBr3Θ both are pyramidal

Topic: Chemistry, Chemical Bonding and Molecular Structure, NEET
The X-shaped structures formed during the largest stage of meiosis-I are called

Options:
A Bivalent
B Chiasmata
C Cross-overs
D More than one option is correct

The correct answer is:
Chiasmata

Solution:
The beginning of diplotene is recognized by the dissolution of the synaptonemal complex and the tendency of the recombined homologous chromosomes of the bivalents to separate from each other except at the sites of crossovers. These X-shaped structures are called chiasmata.

Topic: Biology, Cell Cycle and Cell Division, NEET
The x-t graph of a particle undergoing simple harmonic motion is shown below. The acceleration of the particle at t=23s is

Options:
A 332π2cms2
B -π232cms2
C π232cms2
D - 332 π2cms2

The correct answer is:
-π232cms2

Solution:
Using the general equation of SHM
x=Asinâ¡Ït
as per graph A = 1 cm, T = 8 sec
âw= 2Ï T = Ï 4 x=sin Ï 4 t acceleration a= d 2 x d t 2 âa= â Ï 2 16 sin Ï 4 t at t= 2 3 , a= â Ï 2 16 sin( Ï 4 . 2 3 )= â Ï 2 16 .sin( Ï 6 ) âa= â Ï 2 16 Ã 1 2 = â Ï 2 32 cm/ s 2

Topic: Physics, Oscillations, NEET