00:01
Hello everyone in this problem we have to calculate the resultant force acting on the frame due to forces 300 newton, 500 newton acting at different points so we are replacing these forces by a single force on the frame and we have to calculate moment of these forces about the point a so there are two problems 300 newton force we are naming to be f1 this is to be named f2 and this is to be named f3.
00:35
Now we will write the component of f1, f2 and f3.
00:41
So f1 is at this point.
00:43
This point we are marking to be p point.
00:46
I am writing here this is p point.
00:49
There is a little bit less space here.
00:53
So this is your p point i am marking here.
00:58
This is q point and say this is r point.
01:04
Now, f1, this is the x component of f1 and this will be the y component and this angle is given 30.
01:14
So i am expressing f1 force into component form.
01:18
So it will be 300 cost of 30 i cap minus 300, sine of 30, j cap.
01:36
When you solve it cost 30 is root 3 by 2, you will get 260 newton i cap near above.
01:43
Minus 150 newton j cap this is f1 force say this equation is 1 now f2 force i'm writing here f2 force is along x -axis you may see the figure so this could be written as 500 newton i cap now f3 force is along negative y -axis you may see the figure this is this is the direction negative y axis so you may write minus 4 and 8 j cap newton this is your third now resultant or single force acting on the frame you can write a vector addition of f1 f2 and f3 f1 we have measured 260 newton i cap minus 150 newton j cap, f2 is 500 newton icap, and f3 is minus 400 newton j cap...