A hydrogen atom at rest de-excites from n = 2 state to n = 1 state. Calculate the percentage error in calculation of momentum of photon if recoil of atom is not taken into account. The energy equivalent of rest mass of hydrogen atom is 940 MeV.
1 Answers
The energy of a photon is given as, `Delta E`/atom `= 3.03 xx 10^(-19)J "atom"^(-1)` then, the wavelength `(lambda)` of the photon is
Correct Answer - C (c) According to formula =, `E=(hc)/(lambda)(v=(c)/(lambda))` Energy E=hv `3.03xx10^(-19)=(hc)/(lambda)` `lambda=(6.63xx10^(-34)xx3.0xx10^(8))/(3.03xx10^(-19))` `=6.56xx10^(-7) m` `=6.56xx10^(-7)xx10^(9)nm` =`6.56xx10^(2) nm` `=656 nm`
2 Answers 1 views
The mass of a cube has error of 2% and the length of its edge has error of 1%. What will be the maximum percentage error in calculation of its density
Density of cube `(p)=(M)/(V)=(M)/L^(3)) therefore((Deltap)/(P))_("max")xx100=((DeltaM)/(M)xx100)+3(DeltaL)/(L)xx100)=2%+3(1%)=5%`
2 Answers 1 views
The error in measuring the side of a cube is `+- 1%`. The error in the calculation of the volume of the cube will be about
Volume of cube V- (side `a)^(3)` `therefore V=a^(3)`. Take log and differentiate. `(DeltaV)/(V)=3(Deltaa/(a)=3(+-+-1%)=+-3%`
2 Answers 1 views
A light photon of wavelength `lambda_(0)` is absorbed by an atom of mass m at rest in ground state. The atom is free to move. The atom after absorbing
Correct Answer - `lambda_(0) = (2h)/(sqrt(2mk) + (k)/(c))`
2 Answers 7 views
A hydrogen atom in ground state is moving with a kinetic energy of 30 eV. It collides with a deuterium atom in ground state at rest. The hydrogen atom
Correct Answer - `20 eV, 13.2 eV`
2 Answers 1 views
The first excitation potential of sodium atom is 2.1 V. Calculate the longest wavelength of the emitted photon. Will the photon be visible ? To Which
Correct Answer - 5893 Å
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A hydrogen atom in ground state absorbs a photon of ultraviolet radiation of wavelength `50 nm` Assuming that the entire photon energy is taken up by
Correct Answer - `[11.2eV]`
2 Answers 1 views
The minimum kinetic energy of a ground state hydrogen atom required to have head-on collision with another ground state hydrogen atom but at rest to p
Correct Answer - 20.4 eV
2 Answers 2 views
A stationary hydrogen atom emits a photon corresponding to the first line of the Lyman series. What is the velocity of recoil of the atom? `(m_(H)=1.6
Correct Answer - 3.25 m/s
2 Answers 1 views
If there is an error of 0.1% in the measurement of the radius of a sphere, find approximately the percentage error in the calculation of the volume of
Correct Answer - 0.003
2 Answers 1 views