Novakid HS : Owner and Copyright: Sriparna Mondal

Selina Concise Physics Class 10 All Chapters Please click on the links given alongside the chapters to go to the exercise questions with answers, solved Numericals and other important extra questions from the chapters.   Chapter 1 Force:  http://force-icse-physics  Chapter 2 Work, Energy and Power:  http://work-energy-and-power Chapter 3 Machines:  http://machines-icse  Chapter 4 Refraction of Light at Plane  Surfaces:  http://refraction-of-light-at-plane-surfaces  Chapter 5 Refraction through Lens:  http://refraction-through-lens-selina  Chapter 6 Spectrum:  http://spectrum-selina-physics  Chapter 7 Sound:  http://sound-selina-icse  Chapter 8 Current Electricity:  http://current-electricity-selina  Chapter 9 Electrical Power and Household Circuits:  http://electrical-power-and-household-circuits  Chapter 10 Electro-magnetism:  http://electro-magnetism-selina-icse  Chapter 11 Ca...

Selina ICSE Concise Physics for Class 10 Physics   Chapter 12 Radioactivity Exercise 12(A) 1.Name the three constituent of an atom and state their mass and charge of each. How are they distributed in an atom? Solution 1. Three constituent of an atom are: Electrons: mass is 9.1 x 10-31 kg, charge is -1.6 x 10-19C Neutron: mass is 1.6749 x 10-27 kg, charge is zero. Protons: mass is 1.6726 x 10-27 kg, charge is +1.6 x 10-19 C 2.Define the terms: (a)Atomic number and(b) mass number. Solution 2 . Atomic number –  the number of protons in the nucleus is called atomic number. Mass number –  the total number of nucleons in the nucleus is called mass number. 3.What is nucleus of an atom? Compare its size with that of the atom. Name its constitutents. How is the number of these constituents determined by the atomic number its atomic model. Solution 3. The nucleus at the centre of atom, whose size is of the order of 10-15 m to 10-14 m. The size of a nucleus is 10-5 to 10-4 time...