List of top Physics Questions asked in JEE Main

Which of the following Maxwell's equation is valid for time varying conditions but not valid for static conditions:

Match List-I with List-II

Choose the correct answer from the options given below:

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%  

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.

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: 

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

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. 

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

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 current of 2 A flows through a wire of crosssectional area 25.0 mm2 . The number of free electrons in a cubic meter are 2.0 x 10²⁸ . The drift velocity of the electrons is _____ x 10^-6 ms^-1 (Given, charge on electron = 1.6 x 10^-19C)

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)

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:

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______.

An organ pipe 40cm long is open at both ends. The speed of sound in air is 360ms^-1 . The frequency of the second harmonic is ____Hz.

Two vertical parallel mirrors A and B are separated by 10 cm. A point object O is placed at a distance of 2 cm from mirror A. The distance of the second nearest image behind mirror A from the mirror A is ___cm

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

Experimentally it is found that 12.8 eV energy is required to separate a hydrogen atom into a proton and an electron. So the orbital radius of the electron in a hydrogen atom is\(\frac{ 9}{x} x 10^{-10}\)m. The value of the x is _____.
(1eV = 1.6 x 10^-19J, \(\frac{1}{4π∈_0}\) = 9 x 10⁹ NM² / C² and electronic charge = 1.6 x 10^-19JC)

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

A nucleus with mass number 242 and binding energy per nucleon as 7.6 MeV breaks into fragment each with mass number 121. If each fragment nucleus has binding energy per nucleon as 8.1 MeV, the total gain in binding energy is ____MeV.

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

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:  

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 air bubble of diameter 6 mm rises steadily through a solution of density 1750kg / m³ at the rate of 0.35 cm/s. The co-efficient of viscosity of the solution (neglect density of air) is ____Pas (given, g = 10ms^-2)

An electric dipole of dipole moment is 6.0 x 10^-6 Cm placed in a uniform electric field of 1.5 x 10³ NC^-1 in such a way that dipole moment is along electric field. The work done in rotating dipole by 180º in this field will be _____mJ.