List of top Questions asked in JEE Main- 2023

Let the lines l₁ :  \(\frac{x+5}{3} =\frac{y+4}{1}=\frac{z−α}{−2}\)  and l₂ :3x+2y+z–2=0=x–3y+2z-13 be coplanar. If the point P(a, b, c) on l₁ is nearest to the point Q(-4,-3, 2), then |a| + |b|+|c| is equal to

Let a, b, c be three distinct real numbers, none equal to one. If the vectors \(a\hat{i}+\hat{j}+\hat{k},\hat{i}+b\hat{j}+\hat{k}\) and \(\hat{i}+\hat{j}+c\hat{k}\) are coplanar, then \(\frac{1}{1-a}+\frac{1}{1-b}+\frac{1}{1-c}\) is equal to 

(S1): (p⇒q)∧(p∧((~q)) is a contradiction and
(S2): (p∧q)v((~q)v((~p)∧ q)v (p∧(~q))v((~p)∧ (~q)) is a tautology

Match List I with List II

	List I		List II
A	Spring constant	I	[T-1]
B	Angular speed	II	[MT-2]
C	Angular momentum	III	[ML2]
D	Moment of Inertia	IV	[ML2T-1]

Choose the correct answer from the options given below:

Given below are two statements:
Statement I: A truck and a car moving with same kinetic energy are brought to rest by applying brakes which provide equal retarding forces. Both come to rest in equal distance. 
Statement II : A car moving towards east takes a turn and moves towards north, the speed remains unchanged. The acceleration of the car is zero.  
In the light of given statements, choose the most appropriate answer from the options given below. 

The amplitude of 15sin(1000πt) is modulated by 10sin(4πt) signal. The amplitude modulated signal contains frequency (ies) of
(A) 500 Hz  
(B) 2 Hz  
(C) 250 Hz  
(D) 498 Hz  (E) 502 Hz 
Choose the correct answer from the options given below: 

The ratio of escape velocity of a planet to the escape velocity of earth will be:- Given: Mass of the planet is 16 times mass of earth and radius of the planet is 4 times the radius of earth.

an body cools down from 80°C to 60°C in 5 minutes The temperature pf the surrounding is 20°C. The time taken to cool from 60°C to 40°C is

An engine operating between the boiling and freezing points of water will have  
1. efficiency more than 27%  
2. efficiency less than the efficiency a Carnot engine operating between the same two temperatures.  
3. efficiency equal to 27%  
4. efficiency less than 27%  

A particle is executing Simple Harmonic Motion (SHM). The ratio of potential energy and kinetic energy of the particle when its displacement is half of its amplitude will be

Given below are two statement: one is labelled as Assertion A and the other is labelled as Reason R.  
Assertion A : If an electric dipole of dipole moment 30 x 10-5 Cm is enclosed by a closed surface, the net flux coming out of the surface will by zero.
Reason R : Electric dipole consists of two equal and opposite charges. 
In the light of above, statements, choose the correct answer from the options given below:

A wire of resistance 160 Ω is melted and drawn in wire of one-fourth of its length. The new resistance of the wire will be

Given below are two statements:  
Statement I : The diamagnetic property depends on temperature.  
Statement II : The included magnetic dipole moment in a diamagnetic sample is always opposite to the magnetizing field.  
In the light of given statement, choose the correct answer from the options given below:  

A particle is thrown vertically upward with initial velocity of 150 m/s. Find the ratio of its speed at t = 3 seconds and t = 5 seconds. is \(\frac{x+1}{x}\) the value of x is___. (take g = 10 m/s2)

Three force F₁ = 10N, F₂ = 8 N, F₃ = 6N are acting on a particle of mass 5 kg. The forces F₂ and F₃ are applied perpendicular so that particle remains at rest. If the force F₁ is removed, then the acceleration of the particle is

An ice cube has a bubble inside. When viewed from one side the apparent distance of the bubble is 12 cm. when viewed from the opposite side, the apparent distance of the bubble is observed as 4 cm. If the side of the ice cube is 24 cm, the refractive index of the ice cube is

A proton and an α-particle are accelerated from rest by 2V and 4V potentials, respectively. The ratio of their de-Broglie wavelength is

A 12.5 eV electron beam is used to bombard gaseous hydrogen at room temperature. The number of spectral lines emitted will be

In an n-p-n common emitter (CE) transistor the collector current changes from 5 mA to 16 mA for the change in base current from 100 μA and 200 μA, respectively. The current gain of transistor is______.

Given below are two statement : one is labelled as Assertion A and the other is labelled as Reason R.  
Assertion A : EM waves used for optical communication have longer wavelengths than that of microwave, employed in Radar technology.  
Reason R : Infrared EM waves are more energetic than microwaves, (used in Radar)  
In the light of given statements, choose the correct answer from the options given below:  

A metal chloride contains 55.0% of chlorine by weight. 100 mL vapours of the metal chloride at STP weigh 0.57 g. The molecular formula of the metal chloride is (Given: Atomic mass of chlorine is 35.5u)

For lead storage battery pick the the correct statements.
A. During charging of battery, PbSO4 on anode is converted into PbO2 
B. During charging of battery, PbSO4 on cathode is converted into PbO2 
C. Lead storage battery, consists of grid of lead packed with PbO2 as anode 
D. Lead storage battery has ~ 38% solution of sulphuric acid as an electrolyte 
Choose the correct answer from the options given below:

Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R.
Assertion A: In the Ellingham diagram, a sharp change in slope of the line is observed for Mg → MgO at ~ 1120°C 
Reason R: There is a large change of entropy associated with the change of state. 
In the light of the above statements, choose the correct answer from the options given below : 

Match List I with List II

	List I -Type of Hydride		List II-Example
A	Electron deficient hydride	I	MgH2
B	Electron rich hydride	II	HF
C	Electron precise hydride	III	B2H6
D	Saline hydride	IV	CH4

Choose the correct answer from the options given below:

Given below are two statement: one is labelled as Assertion A and the other is labelled as Reason R.
Assertion A: 5f electrons can participate in bonding to a far greater extent than 4f electrons 
Reason R: 5f orbitals are not as buried as 4f orbitals 
In the light of the above statements, choose the correct answer from the options given below: