Consequences of Uniform Velocity: A Bus Collision

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Discussion Overview

The discussion revolves around the implications of uniform velocity in the context of a bus collision and the resulting forces and injuries. Participants explore concepts related to forces, acceleration, and the nature of motion, touching on both theoretical and conceptual aspects.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • One participant questions how a bus moving with uniform velocity can cause injury during a collision, suggesting that zero acceleration implies zero force.
  • Another participant argues that the change in velocity of a person during the collision results in a large acceleration, which in turn implies a large force acting on the person.
  • Several participants discuss the nature of forces in the universe, proposing that everything has forces acting on it, and that balanced forces can lead to equilibrium.
  • There is a debate over whether objects on Earth are in a state of motion or rest, with some asserting that they are at rest relative to each other while others suggest they are experiencing gravitational acceleration.
  • One participant emphasizes that weight is a result of gravitational acceleration and discusses the relationship between weight and acceleration.
  • Another participant introduces the concept of energy transfer in collisions, referencing kinetic energy as a factor in understanding the impact.

Areas of Agreement / Disagreement

Participants express differing views on the nature of forces, motion, and the implications of uniform velocity. There is no consensus on several points, particularly regarding the interpretation of motion and forces in various contexts.

Contextual Notes

Participants reference various physical concepts such as acceleration, forces, and energy without resolving the complexities involved in these discussions. Some assumptions about the definitions of motion and forces remain unaddressed.

Who May Find This Useful

This discussion may be of interest to those exploring concepts in physics, particularly in relation to forces, motion, and collisions. It may also appeal to individuals curious about the philosophical implications of motion and equilibrium in the universe.

ashisrocking
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Forces ...

this was one question I've always thought upon right from the time i have learned abt forces and velocity .. a bus movin with a uniform velocity has zero acceleration ... then how, in such a case does a person get injure or even die when a bus collides with him ?? if the bus is moving with uniform velocity, there should be zero force and if the force is zero, the person shouldn't be injured or die...
can anyone please help me in this question.??
 
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Assume that the bus doesn't lose any significant velocity after impact. Now look at the CHANGE in velocity of the person. He sent from zero velocity to the same velocity of the bus in less than 1 second! So there's a change in velocity in a very short time, and that means a very large acceleration for him. Consequently, a large force must have been applied to this person. Guess where the force came from?

Zz.
 
is it true to say that everything in the universe has a force acting on it at all times...?

in some cases these forces are balanced therefore the object is in equilibrium and appears to stay still?

is it correct to say everything in the universe is in a state of motion? even an object on the earth... its accelerating down towards the earth... but because the Earth is providing an equal and opposite accelerating force back at it it appears to not be moving?
 
hannah93 said:
is it true to say that everything in the universe has a force acting on it at all times...?

in some cases these forces are balanced therefore the object is in equilibrium and appears to stay still?
True. Gravity is pretty much the weakest of the forces, but it's the only one that has no known counter-force. That's why it dominates on macro scales; the others cancel each other out.

hannah93 said:
is it correct to say everything in the universe is in a state of motion? even an object on the earth... its accelerating down towards the earth... but because the Earth is providing an equal and opposite accelerating force back at it it appears to not be moving?
Everything is in a state of motion relative to something else. An object on the Earth, however, is not accelerating downward nor being accelerated equally upward by the Earth. They are at rest relative to each other. The term 'acceleration' indicates a change of velocity, which neither is experiencing.
 
isn't it experiencing 'g' by virtue of the fact it has weight? - and g is a measure of acceleration?

F=ma? W=mg?
 
and surely the forces are only cancelling each other out if something appears to stay still (in your frame of reference)... if something appears to be moving then the forces aren't balanced - i.e thrust > air resistance for a moving vehicle...?
 
hannah93 said:
isn't it experiencing 'g' by virtue of the fact it has weight? - and g is a measure of acceleration?

Actually, it's experiencing weight because of 'g'. Weight is just the effect of gravity upon mass. I'm not sure of the proper way to phrase this, since I'm not a scientist, but 'g' is a measure of potential acceleration, as well as actual. If you stand at the edge of a cliff, you feel gravity attracting you but you have no acceleration because the ground is holding you up. If you step off, then there's acceleration (followed by an unpleasant negative acceleration a few seconds later).
As for the forces cancelling, what I mean is that for every positve electrical charge (proton), there's a negative one (electron) to counteract it. For every north magnetic pole, there's a south. As far as has yet been verified, there is no 'antigravity'.
 
Last edited:
P=mv
 
Maybe something to do with the energy transfer, K.E.=1/2* m*v^2
 

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