a branch is a mean of preposition & two sticks are rubbing against each other & if two objects are rubbing each other, then they are moving against each other ->  two sticks are moving against each other  one stone are moving against each other & a stick is a kind of object & friction occurs when two object 's surfaces move against each other -> friction will occur between two sticks friction will occur between two sticks  friction will occur between two sticks & slip acid the event of an preposition to decrease & a stick is a kind of object -> friction between two sticks will cause two sticks to increase in temperature friction between two sticks will cause two sticks to increase in temperature  friction between two sticks will cause two sticks to increase in temperature & slip is a mean of willingly -> frictional force between two sticks causes them to increase in temperature