Q1 What is natural radioactivity? Name different types of rays emitted by a radioactive material and give their properties. Solution

Q2 Starting with the law of radioactive disintegration, show that: N = N_oe^-λt where the terms have their usual meaning Solution

Q3 Define half-life of a radioactive substance. Establish a relation between half-life T and decay constant λ Solution

Q4 What do you mean by half-life time of a radioactive element? Explain half-life time and decay constant by drawing a curve between undisintegrated atoms of the element and time. Solution

Q5 What is meant by the activity of a radioactive substance? Draw time-activity graph for a radioactive substance. Find the activity after four half-lives in terms of initial activity. After how much time the activity will become zero Solution