Problem 512 | Friction

Problem 512
A homogeneous block of weight W rests upon the incline shown in Fig. P-512. If the coefficient of friction is 0.30, determine the greatest height h at which a force P parallel to the incline may be applied so that the block will slide up the incline without tipping over.
 

Tall block on an inclined plane

 

Solution 512

 

Hi sir. Good day. Question lang po, hindi po ba may normal force pa rin na kasama kapag nag-slide up ung block sa inclined plane without tipping over? Sinubukan ko po kasi magslide ng block pataas sa incline and nakita ko may mga certain heights din na may tipping at wala kaya confused lang po ako kung bakit natanggal ung normal force sa problem. Naisip ko rin since the block is moving baka kaya neglected ung normal force.