English

In Hydrogen, the electron jumps from the fourth orbit to the second orbit. The wavenumber of the radiations emitted by an electron is ______

Advertisements
Advertisements

Question

In Hydrogen, the electron jumps from the fourth orbit to the second orbit. The wavenumber of the radiations emitted by an electron is ______  

Options

  • `"R"/16`

  • `(3"R")/16`

  • `(5"R")/16`

  • `(7"R")/16`

MCQ
Fill in the Blanks
Advertisements

Solution

In Hydrogen, the electron jumps from the fourth orbit to the second orbit. The wavenumber of the radiations emitted by an electron is `underline((3"R")/16).`

shaalaa.com
  Is there an error in this question or solution?
Chapter 15: Structure of Atoms and Nuclei - MCQ’S

APPEARS IN

SCERT Maharashtra Physics [English] 12 Standard HSC
Chapter 15 Structure of Atoms and Nuclei
MCQ’S | Q 7

RELATED QUESTIONS

Sample of carbon obtained from any living organism has a decay rate of 15.3 decays per gram per minute. A sample of carbon obtained from very old charcoal shows a disintegration rate of 12.3 disintegrations per gram per minute. Determine the age of the old sample given the decay constant of carbon to be 3.839 × 10−12per second.


Complete the following equation describing nuclear decay.

\[\ce{_88^226Ra->_2^4\alpha {+}}\] ______.


Complete the following equation describing nuclear decay.

\[\ce{_8^19O->e^- { +}}\] _____


Complete the following equation describing nuclear decay.

\[\ce{_90^228Th->\alpha { +}}\] _____


Write relation between decay constant of a radioelement and its half-life.


The half-life of 18F is 110 minutes. What fraction of 18F sample decays in 20 minutes?


The half-life of 35S is 87.8 d. What percentage of 35S sample remains after 180 d?


The half-life of radon is 3.82 d. By what time would 99.9% of radon will be decayed?


Show that half life period of radioactive material varies inversely to decay constant λ.


The half-life of a certain radioactive nucleus is 3.2 days. Calculate (i) decay constant (ii) average life of radioactive nucleus.


Obtain an expression for the half-lifetime of radioactive material. Hence state the relation between an average life and half life time of radioactive material.


A radioactive substance decays to (1/10)th of its original value in 56 days. Calculate its decay constant. 


The rate of radioactive disintegration at an instant for a radioactive sample of half-life 2.2 x 109 s is 1010 s-1. The number of radioactive atoms in that sample at that instant is, ______ 


Most excited states of an atom have life times of about ____________.


The activity of a radioactive sample ____________.


What is alpha decay?


The radioactivity of a sample is R1 at a time T1 and R2 at a time T2. If the half-life of the specimen is T, the number of atoms that have disintegrated in the time (T1 - T2) is proportional to ______.


A radioactive element has rate of disintegration 10,000 disintegrations per minute at a particular instant. After four minutes it become 2500 disintegrations per minute. The decay constant per minute is ______.


The activity of a radioactive substance decreases by a factor of 32 in one hour. The half-life of the substance (in min) is ______.


Show that the number of nuclei of a radioactive material decreases exponentially with time.


The half-life of \[\ce{^238_92U}\] undergoing ∝- -decay is 4.5 × 10years. What is the activity of 1g sample of \[\ce{^238_92U}\]?


Define half-life period.


In one mean lifetime of a radioactive element the fraction of the nuclei that has disintegrated is ______. [e is the base of natural logarithm]


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×