$\alpha$-particles can be detected using

Which of the following statements is incorrect regarding cathode rays?

What is a kernel in the context of atomic structure?

The nucleus of an atom can be assumed to be spherical. The radius of the nucleus of mass number $A$ is given by $1.25 \times 10^{-13} \times A^{1/3} \ cm$. The radius of the atom is $1 \ \mathring{A}$. If the mass number is $64$,then the fraction of the atomic volume that is occupied by the nucleus is:

Calculate the ratio of the diameter of an atom to the diameter of its nucleus.

The ratio of specific charge of a proton to that of an $\alpha -$particle is: