Does this mean I can drive like crazy along with everyone else?

[uhrs]

question: Your car is on a crowded highway with everyone heading south at about 100 km/h (62 mph). The car ahead of you slows down slightly and your car bumps into it gently. Why is the impact so gentle?

answer: Your relative velocity is small—in your frame of reference the car in front of you is barely moving, so the impact is very gentle.

[khaled]

Basically, if you and someone else move in the same speed and direction, the relative speed is 0, just like if you both are not moving at all .. if he slows down, it's like if you both were standing and went backward and bumped you, so I guess, he'd bump you at (your speed - his new speed) Km\h, which is negative,

 

I think that if you accelerate and bump into his car with some force, will result different, if he slowed down and bumped your car in the same amount of force ...

[J.C.MacSwell]

question: Your car is on a crowded highway with everyone heading south at about 100 km/h (62 mph). The car ahead of you slows down slightly and your car bumps into it gently. Why is the impact so gentle?

answer: Your relative velocity is small—in your frame of reference the car in front of you is barely moving, so the impact is very gentle.

 

The danger is that the road and surroundings are at 100 km/h relative to you. That little bump can easily misalign the wheels with the road and result in further misalignment and loss of control. From there it's not so much how fast you are moving, but how fast you slow down if you impact some of that "scenery" coming at you at 100 km/h.

 

Compare the same group of cars in outer space all heading "South" at 100 km/h in some reference frame. If they drift together not much happens...after all...relative to each other they are stationary and there is no high energy masses going by them.

Edited August 11, 2011 by J.C.MacSwell

[DrRocket]

The danger is that the road and surroundings are at 100 km/h relative to you. That little bump can easily misalign the wheels with the road and result in further misalignment and loss of control. From there it's not so much how fast you are moving, but how fast you slow down if you impact some of that "scenery" coming at you at 100 km/h.

 

Compare the same group of cars in outer space all heading "South" at 100 km/h in some reference frame. If they drift together not much happens...after all...relative to each other they are stationary and there is no high energy masses going by them.

 

"I was proceeding down the road. The trees on the right were passing me in orderly fashion at 60 miles per hour. Suddenly one of them stepped in my path." -- John von Neumann

[khaled]

Wait a minute, if the crowded street where all cars move at 100 Km\h,

 

if one bumped at the car behind it, the one behind will lose speed, and bump the one behind, the damage will be sequential ...

[hawksmere]

As already stated. The force of the impact is determined by the speed and mass of the two colliding objects. If you are both travelling at say 60 m.p.h and the car in front of you breaks slightly at say 59 m.p.h then the speed of the impact is of the velocity of 1 m.p.h as both are tarvelling at the same speed, both relative to the road.

 

One also has to consider varible vectors as the cars may not be travelling in exactly the same line.

 

Picture the cars being toy cars, both in a box and crash one into the other at around 1 m/p/h. Now take this box and sit in a car tarvelling 60 m/p/h. Mass is obviously different but the speed of impacty is still 1 m/p/h relative to the car you are sitting on.

 

If you, the observer in s sees an object moving along x axis at velocity (w), then you are the 'system (s).Transiting at velocity v in the specific direction x with respect to S (you), You will then see the object moving with the velocity w' where

 

We can therefore do a little math and change the equation....

 

Now that if that object was to move at SPL (speed of light) in the S system (e.g. w = c), it will too be shifting; S' system. Further more, if w & v were small in respect to SPL, we recover the Galilean transformation of velocities: .

 

To simplify ir fuether, (call the system k) travelling north with velocity v with respect to the road (system k). you inside the car throw a ball east with a velocity u in respect road (not your direction should the road bend). Classical physics state, the observer, standing still on the side of the road will measure V (of the ball) of the asv

+ U. Special relativity however proves this as incorrect. Instead, the person standing on the kerb will measure the velocity of the ball as . If u and v are small in comparison to c, then the v + U is valid

 

 

[J.C.MacSwell]

As already stated. The force of the impact is determined by the speed and mass of the two colliding objects. If you are both travelling at say 60 m.p.h and the car in front of you breaks slightly at say 59 m.p.h then the speed of the impact is of the velocity of 1 m.p.h as both are tarvelling at the same speed, both relative to the road.

 

One also has to consider varible vectors as the cars may not be travelling in exactly the same line.

 

Picture the cars being toy cars, both in a box and crash one into the other at around 1 m/p/h. Now take this box and sit in a car tarvelling 60 m/p/h. Mass is obviously different but the speed of impacty is still 1 m/p/h relative to the car you are sitting on.

 

If you, the observer in s sees an object moving along x axis at velocity (w), then you are the 'system (s).Transiting at velocity v in the specific direction x with respect to S (you), You will then see the object moving with the velocity w' where

 

We can therefore do a little math and change the equation....

 

Now that if that object was to move at SPL (speed of light) in the S system (e.g. w = c), it will too be shifting; S' system. Further more, if w & v were small in respect to SPL, we recover the Galilean transformation of velocities: .

 

To simplify ir fuether, (call the system k) travelling north with velocity v with respect to the road (system k). you inside the car throw a ball east with a velocity u in respect road (not your direction should the road bend). Classical physics state, the observer, standing still on the side of the road will measure V (of the ball) of the asv

+ U. Special relativity however proves this as incorrect. Instead, the person standing on the kerb will measure the velocity of the ball as . If u and v are small in comparison to c, then the v + U is valid

 

Why would the mass be different in the new frame of reference?

[hawksmere]

Why would the mass be different in the new frame of reference?

 

Assuming that the force will be different as are the composites of a toys car. I see your point but mass p =mv (p-momentum, v speed and m moving mass) would surely relate to the material in tha mass? Unless i'm wrong. Cars run on conserved energy and the toy cars wouldn't.