Ravi suggested his friend Karim the following ways to reduce or minimise friction. (i) Smoothening the surfaces in contact. (ii) applying lubricants between the surfaces (iii) streamlining the bodies of objects moving in fluids (iv) Applying coarse material between the surfaces is contact. Which of the methods suggest is correct?




Options :
(i) and (iv)
only (iv)
(ii) and (iii)
(i), (ii) and (iii)