Actually rubber has higher electron affinity than wool. So,when they are rubbed together the rubber acquires a few electrons from the wool and the rubber therefore acquires an excess of electrons and is negatively charged, while the wool is left with a deficit of electrons and is therefore positively charged.
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Actually rubber has higher electron affinity than wool. So,when they are rubbed together the rubber acquires a few electrons from the wool and the rubber therefore acquires an excess of electrons and is negatively charged, while the wool is left with a deficit of electrons and is therefore positively charged.