- #1
1MileCrash
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Been reading up on physics out of pure interest, just learning really.
Mainly started special relativity and learning about the inertial frames of reference. I think I understand that, but here's what I don't get.
If from one inertial frame of reference moving at a constant 100 MPH, I toss a ball at a speed of 10 MPH, from my frame of reference the ball has moved at a speed of 10 MPH.
A viewer from a different inertial frame of reference moving at 20 MPH in the same direction as the other reference would witness the same ball traveling at a speed of 90 MPH.
But the speed of light is said to be constant.
So, does that mean that if I am in an inertial reference frame traveling 1/2 the speed of light, and an outside viewer is on a "stationary" reference frame (not sure if such a thing exists, but for simplicities sake..) and I shine a flashlight...
From MY reference frame, traveling 1/2 the speed of light, I "witness" the electromagnetic waves emitted from a flashlight traveling at 3 X 10^8 m/s, correct?
But if someone from a stationary reference framed witnessed my frame of reference traveling at 1/2 speed of light AND witnessed the flashlight, would they also "witness" the electromagnetic waves emitted from the flashlight at a speed of 3X10^8 regardless of the speed of the source (flashlight-1/2 the speed of light)?
Is that what it means for C to be constant? Both viewers see it at C, even if one viewer is traveling with the lightsource at 1/2 the speed of light and the other is stationary, they both witness the light from the flashlight at the same speed?
Mainly started special relativity and learning about the inertial frames of reference. I think I understand that, but here's what I don't get.
If from one inertial frame of reference moving at a constant 100 MPH, I toss a ball at a speed of 10 MPH, from my frame of reference the ball has moved at a speed of 10 MPH.
A viewer from a different inertial frame of reference moving at 20 MPH in the same direction as the other reference would witness the same ball traveling at a speed of 90 MPH.
But the speed of light is said to be constant.
So, does that mean that if I am in an inertial reference frame traveling 1/2 the speed of light, and an outside viewer is on a "stationary" reference frame (not sure if such a thing exists, but for simplicities sake..) and I shine a flashlight...
From MY reference frame, traveling 1/2 the speed of light, I "witness" the electromagnetic waves emitted from a flashlight traveling at 3 X 10^8 m/s, correct?
But if someone from a stationary reference framed witnessed my frame of reference traveling at 1/2 speed of light AND witnessed the flashlight, would they also "witness" the electromagnetic waves emitted from the flashlight at a speed of 3X10^8 regardless of the speed of the source (flashlight-1/2 the speed of light)?
Is that what it means for C to be constant? Both viewers see it at C, even if one viewer is traveling with the lightsource at 1/2 the speed of light and the other is stationary, they both witness the light from the flashlight at the same speed?