Q: A door 1.6 m wide requires a force of 1 N to be applied at the free end to open or close it. The force that is required at a point 0.4 m distance from the hinges for opening or closing the door is
(a) 1.2 N
(b) 3.6 N
(c) 2.4 N
(d) 4 N
Ans: (d)