Samples of two radioactive nuclides A and B are taken. λ_Aand λ_B are the disintegration constants of A and B respectively. In which of the following cases, the two samples can simultaneously have the same decay rate at any time?
(a) Initial rate of decay of A is twice the initial rate of decay of B and λ_A = λ_B
(b) Initial rate of decay of A is twice the initial rate of decay of B and λ_A > λ_B
(c) Initial rate of decay of B is twice the initial rate of decay of A and  λ_A > λ_B
(d) Initial rate of decay of B is same as the rate of decay of A at t = 2h and  λ_A < λ_B

The distance of closest approach of an alpha particle fired towards gold nucleus with kinetic energy k is r₀. The distance of closest approach when the alpha particle is fired towards same nucleus with kinetic energy 4k will be

Find the mass number of an atom whose radius is half of that of a given atom of mass number 192.

A nuclear fusion reaction is given by   If atomic mass of He is 4.0026 amu and that of O is 15.9994 amu then the Q-value of the reaction will be approximately

A radioactive simple is undergoing a decay. At any time t₁, its activity is A and another time t₂, the activity is $\frac{A}{5}.$ <!-- [if gte mso 9]><xml> </xml><![endif]--> What is the average life time for the sample?

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