Question

BASED ON FRICTION1)explain the advantage of streamline shape to birds and aquatic animals. 2)Friction also depends on the shape of an object.Explain.3)How do irregularities in a surface affect force of friction.4)How lubricants affect frictional force

Answer 1

ans is in the above pic...
i hope this helps you:)

Answer 2

1. The shape of birds and certain animals like fishes are called streamline ...whereas we human designed a many things by actually implementing this idea .. Now called as aerodynamics this ideas are use to reduce the friction caused by fluids
2. Yes friction depends on the shape of the body but it doesn't depend on the whole body it actually depends on the shape of body which is in the contact of other body which causes friction
3. No such things exist fully plain or linear those irregularities are seen at the molecular level which causes friction the more the irregularities is the more friction it induces again it depends on the contact areas of the bodies
4. Lubricants are the substance which actually fills the irregularities thus making the body more linear and plain which reduces friction

Thanks