Explain, why it is difficult to open a door by pushing or pulling it near the hinge.

Explanation

Torque acting on the plank of door turns the door. Now `:. vectau = vecr xxvecF= r sin theta = rFsinthetahatn`
`:. vectau` zero. i.e., no Torque
When the door is pulled or pushed near the hinge then perpendicular distence i.e., r is zero
`:.` It is difficult to open the door by doing so.