Finding theta when moment is max

In summary, to achieve the maximum moment, the 4 kN force must be perpendicular to the 20m distance. Using the sine rule and forming a closed triangle, the angle theta was calculated to be 9.2 degrees. However, the given answer is 33.6 degrees. The maximum moment was found to be 80 Nm. The law of sines was applied incorrectly and the pivot point is 1.5 m above the ground.
  • #1
goldfish9776
310
1

Homework Statement


to achieve max moment , the 4 kN must br perpendiclar to 20m , right ? so, i formed a cloased triangle and use sine rule to find the
tetha , 25/ sin90 = 4/sin tetha , i gt my tetha = 9.2 degree , but the ans given is 33.6degree
i gt max moment = 80Nm

Homework Equations

The Attempt at a Solution

 

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  • #2
goldfish9776 said:

Homework Statement


to achieve max moment , the 4 kN must br perpendiclar to 20m , right ? so, i formed a cloased triangle and use sine rule to find the
tetha , 25/ sin90 = 4/sin tetha , i gt my tetha = 9.2 degree , but the ans given is 33.6degree
i gt max moment = 80Nm

Homework Equations

The Attempt at a Solution

You've applied the law of sines incorrectly to this problem. You can't measure the length of one side of a triangle in units of Newtons, and another in units of meters.
 
  • #3
And don't forget that the pivot point is shown as 1.5 m above the ground.
 

What is "Finding theta when moment is max"?

"Finding theta when moment is max" refers to a mathematical process used in engineering and physics to determine the angle at which a structure or object experiences the maximum moment, or force that causes rotation, in a given scenario.

Why is it important to find theta when moment is max?

Knowing the angle at which the maximum moment occurs is crucial in engineering and physics because it helps determine the structural integrity and stability of a system. It can also inform design choices and ensure safety in the construction of buildings, bridges, and other structures.

How is theta when moment is max calculated?

The calculation involves using the principles of statics and trigonometry to analyze the forces and moments acting on a system. By setting the first derivative of the moment equation to zero and solving for theta, the angle at which the moment is max can be found.

What factors can affect theta when moment is max?

The angle at which the moment is max can be affected by the distribution and magnitude of forces, the geometry and material properties of the structure, and external factors such as wind or seismic activity.

Can "Finding theta when moment is max" be applied to real-world situations?

Yes, this concept is commonly used in engineering and physics to analyze and design structures in various fields such as civil, mechanical, and aerospace engineering. It can also be applied to everyday objects such as furniture and sports equipment.

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