earthlight

Swanson, the person who is measuring the speed is on object A. Isn't it his time that matters in the velocity calculation. md65536 let me rephrase the question this way. Supposing there are two stationary objects A and D and object B is moving toward D and a light is being shown from A on B and from D on B. The clocks on A and D are moving at the same speed. Lets say the clock on B is moving slower than on D. That means the clock on B is moving slower than on A since the clocks on A and D are the same. If that were the case though you would measure one of the light beams as going faster than the speed of light.

I'm confused about time dilation. I thought it meant the speed a clock ticks as a function of the speed the clock is moving. Lets say a clock is on an object A that is approaching object B. Lets say someone on Object B shines a light on object A. There will be time dilation due to the speed of object A that will make the speed of light appear to be constant no matter how fast B approaches A. We can describe that as deltaTA/deltaTB. That describes the speed at which the clock is ticking. Lets say someone on object fires an object at 10 miles an hour toward object A. Why doesn't a person on object A measure the speed of the approaching object as 10 * deltaTB/deltaTA. Shouldn't the speed of the clock affect all speed measurements and not just the measurement of the speed of light.