Time for radio signal to get to a receiver

AI Thread Summary
The discussion revolves around calculating the time it takes for a radio signal to travel 17.5 km at the speed of light. The initial calculation using the formula t = d/c yielded an incorrect result of 5.83 x 10^5 seconds, which is approximately 7 days. Upon reevaluation, the correct calculation is 5.83 x 10^-5 seconds. Participants emphasize the importance of understanding the underlying physics concepts rather than just memorizing equations. The conversation concludes with a correction of the initial misunderstanding regarding the time calculation.
Jess_18033152
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Homework Statement


A radio transmitter is located 17.5 km away. The broadcast signals travel at the speed of light (c = 3.00 x 108 m.s-1) through the air towards a radio receiver.

Calculate the time it takes the radio signal to travel from the transmitter to the receiver.

Homework Equations


Not sure on what equation to use in this case?

Thinking;
t = d/c ?

The Attempt at a Solution



t = d/c
= 17500m / (3.00 x 10^8)
= 5.83 x 10^5 s

Not sure whether this is the correct equation to use for this question, if not which equation should I use. From my notes in class I don't have an equation that uses these symbols other than t = d/c
 
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Jess_18033152 said:
5.83 x 10^5 s
This is roughly 7 days. Does it make sense to you that light takes a week to travel a distance of 17.5 km?

Let me also generally say that looking for an equation in notes is not a good way of learning physics. This is particularly true if you are just looking for an equation that ”uses my symbols”. You will learn much better if you try to understand why the equations are what they are. Also, symbols are just notation and there is no guarantee that another text will use the same ones. Meaning is everything.
 
Orodruin said:
This is roughly 7 days. Does it make sense to you that light takes a week to travel a distance of 17.5 km?

Let me also generally say that looking for an equation in notes is not a good way of learning physics. This is particularly true if you are just looking for an equation that ”uses my symbols”. You will learn much better if you try to understand why the equations are what they are. Also, symbols are just notation and there is no guarantee that another text will use the same ones. Meaning is everything.

Sorry the answer was 5.83 x 10^-5 s hahah :), thank you.
 
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