Consider the following statements:
Statement 1: Friction is caused due to interlocking of irregularities present on the surfaces in contact.
Statement 2: Rough surfaces generally have more friction between them.
Which of these statement(s) is correct?
Both the statements are correct.
Friction is caused by the interlocking of irregularities present on the surfaces in contact. Rough surfaces have a large number of irregularities and generally have more friction.
This frictional force increases if the two surfaces are pressed harder. Even surfaces which appear smooth have a large number of minute irregularities present on them. These irregularities lock into one another. Thus, both the statements are correct.