LMS

The Balmer series for hydrogen atom corresponds to electronic transitions that terminate in the state of quantum number n = 2. The longest wavelength of photon emitted is

Shortest wavelength photon in the Balmer series is

The wavelength of last spectral line in Lyman series in of Rydberg constant is 

In which of the following transitions will the wavelength be minimum?

In the general formula in which all the series of hydrogen spectrum is given by: 

The radiations emitted from hydrogen filled discharge tube shows: 

Which of the following series of H-Spectrum lies in ultraviolet region?

The relation for paschen series is given as 

If the radioactive substance reduces to  of its original mass in 40 days then its half-life is

1 micro Curie of radioactivity is equal to

The half-life of radium is about 1600 years. If a rock initially contains 1 g of radium, the amount left after 6400 years will be about: 

Radioactive 90Sr has a half-life of 30 years. What percent of a sample of 90Sr will remain after 60 years?            

A count rate 240 per minute reduce to 30 counts per min in 1 hour. The half-life of source is

210Bi (an isotope of bismuth) has a half-life of 5.0 days. The time for three-quarters of a sample of 210Bi to decay is: 

g- radiation are emitted due to

Absorbed dose is defined as 

Half-life of radon gas is 

One reaction which might be used for controlled nuclear fusion is shown.What is particle X?

Emission of radiation from radioactive element is:

Which of given is correct relation for measuring the value of decay constant.

Half-life of Na-24 is _________ which is used to estimate the volume of blood in patient:

The half-life of   is 5 days, if we start with 50, 000 atoms of this isotopes, the number of atoms left over after 10 days is 

The number of neutron in are:

What is the half-life Iodine I-125?

A beta particle is fast moving electron. During a -decay how the Z and A of nucleus changes?

Thorium is transformed after the emission of b-particle into 

The value of A in the following reaction is 

The relationship between decay constant l and half-life T1/2 of the radioactive substance is

Ten grams of  kept in an open container beta-decays with a half-life of 270 days. The weight of the material inside the container after 540 days will be very nearly

The following represents a sequence of radioactive decays involving two -particles and one particle. 

The percentage of the original of a radioactive material left after five half-lives is approximately:

If 20 g of a radioactive substance reduces to 10 g in 4 minutes, then in what time will 80 g of the same substance reduce to 10 g?

Different radioactive materials have  

The unit of decay constant is:

The isotopes I-131 is used in the treatment of:

cobalt-60 is used for treatment of 

The radioactivity of a nucleus becomes 1/64 of its initial value in 60 seconds. The half-life of nuclide is 

Half-life of a radioactive element is:

There is no change in A and Z of any radioactive element by the emission of

 decays to   by 

A radioactive substance is at t=0, the number of atoms is 8×10⁴. Its half-life period is 3 years. The number of atoms 1×10⁴will remain after interval

The decay constant of radium is 4.28×10^-4 per year. Its half-life will be

A sample contains 16 gm of a radioactive material, the half-life of which is two days. After 32 days, the amount of radioactive material left in the sample is

Half-life of a radioactive substance is T.  The time taken for all the nuclei to disintegrate will be

For skin cancer which of following can be used: 

The half-life of a radioactive element which has only 1/32 of its original mass left after a lapse of 60 days is 

Radioactivity is 

The atomic number of an element is:                                                      

Wave length of photon produced due to transition of electron from higher level E2 to E1 is

In which radioactive disintegration, neutron dissociates into proton and electron