What does D′Alembert’s principle state that “The system of forces acting on a body in motion and the Inertia force of the body is in dynamic equilibrium”
![D′Alembert’s Principle](https://cdn-0.extrudesign.com/wp-content/uploads/2019/09/D-Alembert’s-Principle-extrudesign.com-235002.jpg)
But how does this helpfull? Where it is applied?
Do you know Newton’s second law (Law of acceleration)? What did it state?
It states F=ma.
Whereas
- F = Resulting force acting on the body
- m = Mass of the body
- a = Linear acceleration of the centre of mass of the body
F=ma
Mathematically we can write the following
F-ma = 0
This we can frame as F as the resultant force and ma is the forces acting on the body. Both these two forces will be in equilibrium. This is what D′Alembert’s Principle states.
And yes D-Alembert’s Principle is another form of Newton’s second law. It is also known as the Lagrange–d’Alembert principle, and it is also the fundamental laws of motion.
Very helpful for me as a practising student engineer
Thanks