You are here


Three forces are applied to a tree sapling, as shown in Fig. 9–46, to stabilize it. If $\vec{F} \!_A = 385 \textrm{ N}$ and $\vec{F} \!_B = 475 \textrm{ N}$, find $\vec{F} \!_C$ in magnitude and direction.

Problem 1.

Figure 9-46.

Source: Giancoli, Douglas C., Physics: Principles with Applications, 7th Edition, 2014.

Quick Answer: 

$528 \textrm{ N, } 120^\circ \textrm{ cw from } F_A$
(there is a small error in the video at 4:42. When adding $90^\circ$ to $29.73^\circ$ the rounded answer should be $120^\circ$, not $130^\circ$)

Giancoli 7th Edition, Chapter 9, Problem 1


Chapter 9, Problem 1 is solved.

View sample solution


I think this is supposed to be 120 degrees cw from FA

Hi Ijn8, thanks a lot for noticing that. I have updated the written answer, and made a note that there is an error in the video with the final addition of the angles.

All the best,
Mr. Dychko