The constant of motion of a free fall body

AI Thread Summary
In the discussion on the constants of motion for a free-falling body, the key points revolve around identifying these constants in one-dimensional motion. Initial velocity and initial displacement are proposed as constants of motion, but their relationship to total energy is examined, indicating they are not independent. The conversation suggests that while initial velocity and displacement can be treated as constants, their connection to energy must be acknowledged. Additionally, the discussion raises the question of whether these constants correspond to any symmetry within the free-fall system. Overall, the exploration highlights the interplay between these variables in understanding motion in free fall.
jomoonrain
Messages
31
Reaction score
0
1.what are the the constants of motion of a free fall body(treat this as a one-dimension motion,so there are two [independent] constants of motion )?

2.are they initial velocity and initial displacement?

3.and i know the total energy(T+V) is one,but they are not independent with the initial velocity and initial displacement, isn't it?

4.so i means can we just treat the initial velocity and initial displacement as constants of motion ?

5.if we can,do these constant of motin (initial velocity and initial displacement) correspond to some symmetry of the system (free fall body)?

thanks
 
Last edited:
Physics news on Phys.org
The rope is tied into the person (the load of 200 pounds) and the rope goes up from the person to a fixed pulley and back down to his hands. He hauls the rope to suspend himself in the air. What is the mechanical advantage of the system? The person will indeed only have to lift half of his body weight (roughly 100 pounds) because he now lessened the load by that same amount. This APPEARS to be a 2:1 because he can hold himself with half the force, but my question is: is that mechanical...
Some physics textbook writer told me that Newton's first law applies only on bodies that feel no interactions at all. He said that if a body is on rest or moves in constant velocity, there is no external force acting on it. But I have heard another form of the law that says the net force acting on a body must be zero. This means there is interactions involved after all. So which one is correct?
Thread 'Beam on an inclined plane'
Hello! I have a question regarding a beam on an inclined plane. I was considering a beam resting on two supports attached to an inclined plane. I was almost sure that the lower support must be more loaded. My imagination about this problem is shown in the picture below. Here is how I wrote the condition of equilibrium forces: $$ \begin{cases} F_{g\parallel}=F_{t1}+F_{t2}, \\ F_{g\perp}=F_{r1}+F_{r2} \end{cases}. $$ On the other hand...
Back
Top