Physics-
General
Easy
Question
When a hydrogen atom, initially at rest emits, a photon resulting in transition n = 
= 1, its recoil speed is about
- 4.2 m/s
The correct answer is: 4.2 m/s
Related Questions to study
Physics-
Electron in a hydrogen atom is replaced by an identically charged particle muon with mass 207 times that of electron. Now the radius of K shell will be
Electron in a hydrogen atom is replaced by an identically charged particle muon with mass 207 times that of electron. Now the radius of K shell will be
Physics-General
physics-
Consider the following electronic energy level diagram of H-atom: Photons associated with shortest and longest wavelengths would be emitted from the atom by the transitions labelled:
Consider the following electronic energy level diagram of H-atom: Photons associated with shortest and longest wavelengths would be emitted from the atom by the transitions labelled:
physics-General
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In a photoelectric experiment, electrons are ejected from metals X and Y by light of intensity I and frequency f. The potential difference V required to stop the electrons is measured for various frequencies. If Y has a greater work function than X; which one of the following graphs best illustrates the expected results?
In a photoelectric experiment, electrons are ejected from metals X and Y by light of intensity I and frequency f. The potential difference V required to stop the electrons is measured for various frequencies. If Y has a greater work function than X; which one of the following graphs best illustrates the expected results?
Physics-General
physics-
In a photoelectric experiment, the potential difference V that must be maintained between the illuminated surface and the collector so as just to prevent any electron from reaching the collector is determined for different frequencies f of the incident illumination. The graph obtained is shown. The maximum kinetic energy of the electrons emitted at frequency f1 is
In a photoelectric experiment, the potential difference V that must be maintained between the illuminated surface and the collector so as just to prevent any electron from reaching the collector is determined for different frequencies f of the incident illumination. The graph obtained is shown. The maximum kinetic energy of the electrons emitted at frequency f1 is
physics-General
Maths-
then I equals
then I equals
Maths-General
Maths-
dx is equal to
dx is equal to
Maths-General
Maths-
then A+B+C is equal to
then A+B+C is equal to
Maths-General
Physics-
A body of mass 10 kg is moving with a constant velocity of 10 m/s. When a constant force acts for 4 seconds on it, it moves with a velocity 2 m/sec in the opposite direction. The acceleration produced in it is :
A body of mass 10 kg is moving with a constant velocity of 10 m/s. When a constant force acts for 4 seconds on it, it moves with a velocity 2 m/sec in the opposite direction. The acceleration produced in it is :
Physics-General
physics-
A particle moves along the sides AB, BC, CD of a square of side 25m with a velocity of 15 ms–1 Its average velocity is :
A particle moves along the sides AB, BC, CD of a square of side 25m with a velocity of 15 ms–1 Its average velocity is :
physics-General
physics-
Acceleration–time graph of a body is shown. The corresponding velocity–time graph of the same body is :
Acceleration–time graph of a body is shown. The corresponding velocity–time graph of the same body is :
physics-General
physics-
The graph of displacement u/s time is,
Its corresponding velocity–time graph will be :
The graph of displacement u/s time is,
Its corresponding velocity–time graph will be :
physics-General
physics-
Figure (i) and (ii) below show the displacement–time graphs of two particles moving along the x–axis. We can say that :
i) 
ii) 
Figure (i) and (ii) below show the displacement–time graphs of two particles moving along the x–axis. We can say that :
i)
ii)
physics-General
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The displacement versus time graph for a body moving in a straight line is shown in figure. Which of the following regions represents the motion when no force is acting on the body :
The displacement versus time graph for a body moving in a straight line is shown in figure. Which of the following regions represents the motion when no force is acting on the body :
physics-General
physics-
The displacement of a particle as a function of time is shown in the figure. The figure shows that
The displacement of a particle as a function of time is shown in the figure. The figure shows that
physics-General
Physics-
The variation of velocity of a particle with time moving along a straight line is illustrated in the following figure. The distance travelled by the particle in four seconds is :
The variation of velocity of a particle with time moving along a straight line is illustrated in the following figure. The distance travelled by the particle in four seconds is :
Physics-General
