Question

When a hard rubber rod is given a negative charge by rubbing it with wool:
A) Positive charges are transferred from rod to wool.
B) Negative charges are transferred from rod to wool.
C) Positive charges are transferred from wool to rod.
D) Negative charges are transferred from wool to rod
E) Negative charges are created and stored on the rod.

Answer 1

Hint:When a rubber rod is rubbed with fur or felt electrons are transferred from the material to the rod, giving the rod a negative charge. Two negatively charged objects repel. When a positively charged object is brought near a negatively charged object the two objects attract one another. Hence we can choose from the option using the above concept.

Complete step by step solution:
The easiest way to obtain an electric charge is to take any two materials and rub them together. It is noted that one of the materials becomes negatively charged and the other positively charged. For example, if we rub a hard rubber rod with a woolen cloth, the rubber rod acquires a negative charge and the wool an equal amount of positive charge. The charge we call negative is a matter of convention, but with the proposed convention here it is the rubber that becomes negative.
It is known that all matter contains positive and negative charges. The positive charge is very deep inside each atom on the atomic nucleus, while the negative charge is on the electrons that orbit outside the nucleus. Normally, in neutral matter the amounts of positive and negative charges are equal, and we are unaware of either. Given any two materials, it usually happens that one has a greater attraction towards electrons than the other; when the two are rubbed together, the material with higher affinity arrests a few electrons from the material with lower affinity. For example, rubber has a higher electron affinity than wool; when they are rubbed together the rubber captures a few electrons from the wool; the rubber, therefore, obtains an excess of electrons and is negatively charged, while the wool is left with fewer electrons and is positively charged.

Hence, Option D is correct.

Note:In Positively charged particles, the number of positive ions is more than the number of negative ions. This means that the number of protons is more than the number of electrons. To neutralize positively charged particles, electrons from the locality come to this article until the number of protons and electrons become equal. Similarly, negatively charged particles' number of electrons is larger than the number of protons. To neutralize negatively charged particles, because protons cannot move and cannot reach negatively charged particles, electrons move to the ground or any other particle around. In neutral particles, it involves an equal number of protons and electrons. They have both protons, neutrons, and electrons but the number of positive ions is equal to the number of negative ions.