An electron with a velocity of 10^7 m/s enter into a region of magnetic flux density of 0.10T, the angle between the direction of the field and the initial path of electron being 25°.Find the axial distance between two turn of the helical path

Daughter element the new element produced along with a decay particle in a nuclear transmutation 2. half-life the substance that decays in a nuclear transmutation 3. parent element the change of one chemical element into another by nuclear decay or radioactive bombardment 4. transmutation the time required for the decay of one-half of the atoms in a sample of radioactive material