2. One gram of (94)Pu(239) is a alpha emmiter with a half life of 24400 years.given 1g sample of this plutonium how many alpha particles will emit per second

Q. An 'n' number of $\alpha -particles$ per second are being emitted by B atoms of a radioactive element. The half-life of element will be

Q. The luminous dials of watches are usually made by mixing a zinc sulphide phosphor with an $\alpha -particle$ emitter. The mass of radium (mass number $226$, half-life $1620$ years) that is needed to produce an average of $10$ $\alpha -particles$ per second for this purpose is

Q. A sample originally contained ${10}^{20}$radioactive atoms, which emit $\alpha$ -particles emitted inthe thirdyear to that emitted during the second year is $0.3$.How many $\alpha$ particles were emitted in the first year?

Q. A sample $Q$ has half life $20\text{min}$. It decays by emitting alpha particle and beta particle with probability of $60\%$ and $40\%$ respectively.
Initial sample of $Q$ contains $1000$ nuclei, then number of $\alpha -$ particle decay after one hour will be

Q. A $\beta$-particle emitter has a half life of $60.6$ $min$. At any instant of time, a sample of this element registers $2408$ counts per second. Calculate the counting rate after $1.5$ hours.