I didn't understand this concept please explain with brief explanation.

mg Fsin 0 F Fsin0 Fcose fL TN TN () (b) Fig. 1.5 1.11 MOTION ON HORIZONTAL PLANE II Case (i) Let a = acceleration of block to the right Here, ma = F cos e -f F cos 0 - uN = F cos 0 (mg - F sin 0 ) =F (cos e + u sin 0) mg Fsin 0 F (or) a = F (cos e + u sin )- Hg m Fcos0 For minimum force to provide limiting motion, f H mg (F)min= cos0+ usine mg cose V mg Fig. L6 + sin 0 Again for a particular requirement, F will be minimum, cos e when, + sine is minimum, -sin 0 d(cose +sin0 0 (or) + cos e 0 (or) tan 0 u i.e., de mg mg 1+u2 1 . (F)min umg/1+u? 1+u? umg (or) Fmin /1+p? se can Case (i) Applying a Horizontal Force Consider a body of mass "m" lying on a horizontal