Why Does My Statics Solution Differ from the Textbook's Answer?

[physstudent1]

Homework Statement

Determine and locate the resultant R of the two forces and one couple acting on the I beam.

---x

====|====O====|

I understand this is kind of hard to understand this is the best I could do "====" = 3 ft
first | = 6kN force upwards
O= couple 52kN m ccw
second | = 10kN downards

Homework Equations

The Attempt at a Solution

I chose to move all the forces to b where the couple was so that I wouldn't have to wry about the force caused by said couple when finding the resultant. The resultant would then be 4kN down at 6m. However the book says the answer is 4kN down at 5m I am really confused can somebody please help me if you need more help to understand the question please ask.

 

[PhanthomJay]

Homework Statement

Determine and locate the resultant R of the two forces and one couple acting on the I beam.

---x

====|====O====|

I understand this is kind of hard to understand this is the best I could do "====" = 3 ft
first | = 6kN force upwards
O= couple 52kN m ccw
second | = 10kN downards

Homework Equations

The Attempt at a Solution

I chose to move all the forces to b where the couple was so that I wouldn't have to wry about the force caused by said couple when finding the resultant. The resultant would then be 4kN down at 6m. However the book says the answer is 4kN down at 5m I am really confused can somebody please help me if you need more help to understand the question please ask.

You did a good job explaining the problem. But I am not sure what you mean by moving the forces to b. The resultant force must be 4kN down as you noted, but you must correctly determining its location by first summing moments about any point, including the couple, (which just adds or subtracts from the moments of the forces), then solve for the distance the 4kN resultant must be from that point in order to get the same summed moments.

 

[piercas]

I would approach this problem by first drawing a clear and accurate diagram of the I beam and all the forces acting on it. This will help to visualize the problem and identify any potential errors in the given information.

Next, I would use the laws of statics and the principles of vector addition to determine the resultant R of the two forces and one couple. This would involve breaking down the forces into their components, using trigonometry to find the magnitude and direction of each component, and then adding them together to find the resultant R.

In this case, the resultant R should be a downward force with a magnitude of 4kN, acting at a distance of 5m from the left end of the beam. This is because the 6kN upward force and the 10kN downward force cancel each other out, leaving only the 4kN downward force from the couple.

It is important to double check all calculations and units to ensure accuracy. If the book's answer is different from the one obtained, it may be worth rechecking the calculations or seeking clarification on the given information. It is also helpful to discuss the problem with peers or instructors to gain different perspectives and approaches to solving it.