An object is in equilibrium under four concurrent forces in the directions shown in figure. Find the magnitudes of F1 and F2.
Category
📚
LearningTranscript
00:00Hey guys, always try to make your Tuesday better.
00:05Trust me, the rest of your workday will automatically become interesting.
00:11Is this question interesting enough for our minds?
00:15A particle is subjected to some forces.
00:19This particle is not moving at all.
00:23Well, we are asked to get the magnitude of two unknown forces.
00:30Let's discuss this in more detail.
00:34Based on the concept of force equilibrium,
00:37an object will not move anywhere when the resultant force acting on it is zero.
00:43How about we put this system into two-dimensional Cartesian coordinates?
00:48Where the particle is right at the center of coordinates.
00:54Next, resolve all the forces to be parallel to the x-axis or parallel to the y-axis.
01:03The resultant force acting on the particle is zero.
01:07That means sigma fx is equal to zero.
01:13There are three force components there.
01:16Plus 6 root 3, plus 8 cosine 30, and minus f2 cosine 60.
01:22The positive sign means the force is going to the right or east.
01:29The cosine of 30 is half the root of 3 and the cosine of 60 degrees is half.
01:37This is an easy calculation.
01:40F2 is equal to 20 root 3 Newtons.
01:46For the resultant in the vertical direction, sigma fy is equal to zero.
01:52In this direction, there are also three components of force.
01:57Plus f1, plus 8 sine of 30 degrees, minus f2 sine of 60 degrees.
02:06We already know the value of sine of 30 degrees and sine of 60 degrees.
02:12From here, f1 is equal to 26 Newtons.
02:18This is the answer to this question.
02:22Happy learning everyone!