Copper rod cannot be charged easily by friction because it is a conductor. Only non-conducting materials can be charged easily by friction.

When any of these materials are rubbed together, the one in higher order gets positive charge (+) and the one in the lower order gets negative charge (-). The correct frictional order is: glass, wool, ebonite and plastic.

By convention, glass acquire higher order than silk as losses electron. So, on rubbing, glass acquires positive charge and silk acquires negative charge.

Plastic comes below fur in the frictional series of electric charges. So, fur will get positive charge and plastic rod will get the negative charge.

When two bodies are rubbed for charging, the one acquiring positive charge comes first, on a higher position, in electrostatic series. From the series, it may be interpreted that if two objects are rubbed with each other, the one coming higher in the series will acquire positive charge and the other coming lower in the series will acquire negative charge.

For most of the materials, if those are rubbed with materials occurring higher in electrostatic series, will acquire negative charge. And if those materials are rubbed with materials occurring lower in electrostatic series, will acquire positive charge. Dry human skin, occurring at top of the electrostatic series will always acquire positive charge. Teflon, occurring at the bottom of the electrostatic series will always acquire negative charge.

When the forearm is rubbed with a cloth of silk, the dry forearm acquires positive charge. So, all the hairs there acquire same positive charge and repel each other. Thus the hairs stand straight after rubbing.

Static charges are generated by rubbing or friction.

When rubbed with silk, glass and plastic acquire opposite charges. So, the glass rod and the plastic straw, after being rubbed by silk, will attract each other.

The balloons will be seen to repel each other as both are charged with same polarity.

Both of them, refill as well as polythene, gets charged by friction.

Static electricity, while combing dry hair, is generated by friction between comb and dry hair.

Moving charges constitute electric current.

When rubbed by wool, glass becomes positive and rubber becomes negative. Opposite charges attract. So, the balloon and the glass tumbler will attract each other.

A pre-charged electroscope detects the nature of charge on a charged body.

Conduction is the process in which uncharged object acquires charge when it it brought in contact with the charged object.

Because the charges on foil strips gets discharge through air body as soon as paper clip of electroscope is touched by hand, the foil strips collapse.

When a charged body comes close to an electroscope, charges are induced to the electroscope. These charges flow down to the metal strips which open up due to repulsion for having similar charges.

When a charged body is brought near the top conducting disc of an electroscope, the disc gets induced with charges. These charges run down to the metal strips hanging from the paper clip. Now as both the strips get similar charge, those repel each other and thus open up.

Earthing is important for the protection of human life as well as property. For discharging of charges to the Earth some conductor is required, so that electric charges gets conducted into the Earth.

The nature of charge will be negative. Here charging is taking place due to contact and metal paper clip will bear the same charge as the charged body. This is charging by conduction.

If an object is charged by contact or conduction, it acquires the same charge as the charged object.

When we touch the strips, the charges get discharged through our body to the Earth and this process is known as earthing.

When a charged object comes in contact with the Earth, the charges flow into the Earth and the body gets discharged. This process is called earthing.