Question
Describe the two experiments related to static friction with diagram.
✓
Answer
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►It was observed that if two glass rods rubbed with wool or silk cloth are brought close to each other, they will repel. [Fig. (a)].
►The two strands of wool or two pieces of silk cloth, with which the rods were rubbed, also repel each other.
►The glass rod and wool are attracted to each other.
►Similarly, two plastic rods rubbed with cat's fur will repell each other [Fig. (b)] but attract the fur.
►On the other hand, the plastic rod attracts the glass rod [Fig. (c)] and repels the silk or wool with which the glass rod is rubbed. The glass rod repels the fur.
►It was observed that if two glass rods rubbed with wool or silk cloth are brought close to each other, they will repel. [Fig. (a)].
►The two strands of wool or two pieces of silk cloth, with which the rods were rubbed, also repel each other.
►The glass rod and wool are attracted to each other.
►Similarly, two plastic rods rubbed with cat's fur will repell each other [Fig. (b)] but attract the fur.
►On the other hand, the plastic rod attracts the glass rod [Fig. (c)] and repels the silk or wool with which the glass rod is rubbed. The glass rod repels the fur.
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