What is the magnitude of the Reaction Force?

[jj8890]

Homework Statement

In my homework we are asked to find the magnitude of the reaction force at the pivot at a instant and earlier in the problem we found the magnitude of the angular speed at one instant, the magnitude of the angular acceleration at the same instant, and the magnitude of the acceleration of its center of mass at the same instant. I have attached the diagram but basically I am not sure exactly what the magnitude of the reaction force is, we haven't talked about it in class. Could someone clarify this for me?

 

[Doc Al]

At any given instant, the pivot exerts some force on the rod. That's what they are calling the "reaction" force. Figure it out using Newton's 2nd law.

 

[Moetasim]

The magnitude of the reaction force is the amount of force exerted by a support or pivot in response to an applied force or motion. In this case, it refers to the force exerted by the pivot on the object at a specific instant in time. It is equal in magnitude but opposite in direction to the force applied by the object on the pivot. This reaction force is necessary to maintain the object's equilibrium and prevent it from falling or moving in an unintended direction. To calculate the magnitude of the reaction force, you can use Newton's third law of motion, which states that for every action, there is an equal and opposite reaction. Therefore, the magnitude of the reaction force can be determined by using the magnitude of the applied force or motion at the pivot and taking into account the object's mass and acceleration. I hope this clarifies the concept of reaction force for you.