How Does Newton's Second Law Explain Equilibrium and Changes in Apparent Weight?

  • Thread starter Thread starter vinny380
  • Start date Start date
  • Tags Tags
    Law Second law
AI Thread Summary
To achieve equilibrium with a net force of 125 N acting on an object, a force of -125 N must act in the opposite direction. This indicates that equilibrium requires equal and opposite forces to balance out any net force. In the case of an elevator slowing to a stop, while a person's weight remains constant, their apparent weight fluctuates due to acceleration. As the elevator ascends, apparent weight increases, and when it decelerates to a stop, it returns to normal weight. The discussion emphasizes the relationship between force, acceleration, and perceived weight changes in varying conditions.
vinny380
Messages
29
Reaction score
7
Can anyone please help me with these two problems?? I have been trying to figure them out for a while, but cant...

1. A net force of 125 N acts on an object. Find the single force that will produce equlibrium?
Is the answer a force of -125N acting back on the object?? Seems
to easy =/

2. An elevator is traveling from the lobby to the top of a building. As it slows to a stop on the top floor, what happens to your apparent weight?
The question is kind of confusing - I know that on the way up, your apparent weight will be higher than your normal weight...but when it comes to a stop ... wouldn't it be the same as weight??
 
Physics news on Phys.org
1. It depends on what is meant by equilibirium. If equilibrium infers no acceleration or a balance of forces, then and equal force must oppose the other force, and in this case 125 N requires 125 N in the opposite (-) direction.

As for the second problem, obviously one's weight does not change, but the initially the elevator must accelerate against one's weight to obtain some velocity. So one feels heavier. Then at constant velocity (in the gravitational field) one feels normal.

What happens at the top as one approaches the end of the journey?
 
Thread 'Collision of a bullet on a rod-string system: query'
In this question, I have a question. I am NOT trying to solve it, but it is just a conceptual question. Consider the point on the rod, which connects the string and the rod. My question: just before and after the collision, is ANGULAR momentum CONSERVED about this point? Lets call the point which connects the string and rod as P. Why am I asking this? : it is clear from the scenario that the point of concern, which connects the string and the rod, moves in a circular path due to the string...
Thread 'A cylinder connected to a hanged mass'
Let's declare that for the cylinder, mass = M = 10 kg Radius = R = 4 m For the wall and the floor, Friction coeff = ##\mu## = 0.5 For the hanging mass, mass = m = 11 kg First, we divide the force according to their respective plane (x and y thing, correct me if I'm wrong) and according to which, cylinder or the hanging mass, they're working on. Force on the hanging mass $$mg - T = ma$$ Force(Cylinder) on y $$N_f + f_w - Mg = 0$$ Force(Cylinder) on x $$T + f_f - N_w = Ma$$ There's also...
Back
Top