A glass rod is rubbed with silk. Regarding above process which statement is true

A glass rod is rubbed with silk:- Name the scientist who establish the above said type of charges.

Which of the following statements is true?

A glass rod is rubbed with silk:- Is the mass of a body affected on charging?

A glass rod rubbed with silk is brought close to two uncharged spheres in contact with each other, inducing charges on them as shown in figure. Describe what happen when:- The glass rod Is subsequently removed.

A glass rod rubbed with silk is brought close to two uncharged spheres in contact with each other, inducing charges on them . Describe what happen when:- The spheres are separated far apart.

Which of the following statements is not true?