Answer:
4. |R| = 60.8 N (3 s.f.)
θ = 34.7° (3 s.f.) relative to the x-axis
5. |F| = 60.8 N (3 s.f.)
θ = 214.7° (3 s.f.) relative to the x-axis
Step-by-step explanation:
![\textsf{Force}: \quad F=xi+yj](https://img.qammunity.org/2023/formulas/physics/college/29tbms3wanim36iyea630hcvqyser3oyiz.png)
![\textsf{Magnitude}: \quad |F|=√(x^2+y^2)](https://img.qammunity.org/2023/formulas/physics/college/pn4t6j7smz07u7rf1cc31d4qe78f3djlul.png)
Given:
![|F_1|=30\;\sf N](https://img.qammunity.org/2023/formulas/physics/college/awenckenbwl98yn9910s5ybz7ndnwazpfz.png)
![|F_2|=40\;\sf N](https://img.qammunity.org/2023/formulas/physics/college/bf15pzgcbsi8z92rmosidvjxyhpyq21gy9.png)
Using the given magnitudes and the force diagram:
![F_1=30i+0j](https://img.qammunity.org/2023/formulas/physics/college/glvcodp9t3te520p5euxvadep1n1ty3oz0.png)
![\begin{aligned}F_2&=(40 \cos 60^(\circ))i+(40 \sin60^(\circ))\\ &=20i+20√(3)j\end{aligned}](https://img.qammunity.org/2023/formulas/physics/college/j1rolluzw56xzv7ma6ml0k6h4mtj3huht7.png)
Question 4
The resultant force is the sum of all forces acting on an object.
To find the resultant force, add the corresponding components of the forces:
![\begin{aligned}\implies R& =(x_(F_1)+x_(F_2))i+(y_(F_1)+y_(F_2))j\\ &=(30+20)i+(0+20√(3))j\\& = 50i+20√(3)j\end{aligned}](https://img.qammunity.org/2023/formulas/physics/college/8synv2uc1w00ybrhxiftqxe8chypdn63d3.png)
Therefore the magnitude of the resultant force is:
![\begin{aligned}\implies |R|&=\sqrt{50^2+(20√(3))^2\\& = √(2500+1200)\\& = √(3700)\\ & = √(100 \cdot 37)\\ & = √(100)√(37)\\ & = 10√(37)\\ & = 60.8\; \sf N\;(3\:s.f.)\end{aligned}](https://img.qammunity.org/2023/formulas/physics/college/xvmt4fvn89lpoupltqpirnygdhv0dr0osh.png)
The direction of the resultant force is:
![\begin{aligned}\implies \theta & = \tan^(-1)\left((y)/(x)\right)\\\theta & = \tan^(-1)\left((20√(3))/(50)\right)\\\theta & =34.71500395...^(\circ)\\\theta & =34.7^(\circ)\; \sf (3 \:s.f.)\end{aligned}](https://img.qammunity.org/2023/formulas/physics/college/cj4780hc44u4o5hmwz07ghn9pwrfpmvbuz.png)
Question 5
An object is in equilibrium if the resultant force on it is zero.
Therefore, the magnitude of the equilibriant force is equal to the magnitude of the resultant force: 60.8 N (3 s.f.).
The direction of the equilibriant force is opposite to the resultant force, so its components will be:
![F=-50i-20√(3)j](https://img.qammunity.org/2023/formulas/physics/college/4uo6jamte30cohknukxtqj88x3bqszeja7.png)
Therefore, it will be in Quadrant III.
So the direction relative to the x-axis will be the same direction as the resultant force plus 180°:
![\begin{aligned}\implies \theta &=180^(\circ)+34.7^(\circ)\\& = 214.7^(\circ)\; \sf (3 \:s.f.)\end{aligned}](https://img.qammunity.org/2023/formulas/physics/college/92c39byiq7rxjfe2q689rxwnfo7rv4pb9y.png)