Another way you could also solve this question is to break the Nw force into component forces. One that is at right angles to the ladder and one in line with the ladder. The part of the force that is in line with the ladder will have no turning moment, the part of the force that is at right angles with the ladder will be multiplied by the length of the ladder. The reason why I haven't used the hypotenuse (length of ladder) is because the force Nw is not at right angles with the ladder. I hope this helps.
Hi all, there is a typo in the question which should state the static friction coefficient is 0.4 (not 0.4 N)
why is the radius you used for the third term for your fourth equation the y axis distance and not your hypotenuse length?
Another way you could also solve this question is to break the Nw force into component forces. One that is at right angles to the ladder and one in line with the ladder. The part of the force that is in line with the ladder will have no turning moment, the part of the force that is at right angles with the ladder will be multiplied by the length of the ladder.
The reason why I haven't used the hypotenuse (length of ladder) is because the force Nw is not at right angles with the ladder.
I hope this helps.
Thank you very much sir. This video is really helpful especially in my engineering physics class.