Question

4. The diagram below shows two metal spheres mounted on portable insulating supports. A student is given a glass rod and a piece of silk. Without allowing any contact between the glass rod or silk piece with any of the spheres, describe how the student can charge the two spheres with equal but opposite charges. ​

Answer 1

Answer:

By using friction between glass rod and cotton

Explanation:

Use the cotton against glass rod to heat it up .Now after gaining heat energy the outermost electrons transfer from cotton to rod making it as negative charged, so using the method of polarisation ie.charging by induction we make the glass rod( negatively charged ) to come enough close to any of the sphere which will create the other electrons of the sphere chosen to move apart from positive charge making the sphere chosen to get polarised.

Now bring the cotton( positively charged ) to other sphere this will make the other sphere to get positively polarised hence you obtain an equal and opposite charged spheres.

Method of Polarisation can be seen in image provided.