Trying to understand Special Relativity

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simpleton
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Hi,

I was reading on special relativity and was trying to understand it. However, I am still not very sure about the concepts. For example, I have this problem:

I have 2 spaceships, A and B, traveling towards each other. Both have rest length x and speed v, where v is near the speed of light. Both are getting bombarded by photons that travel perpendicular to the direction of the spaceships.

The person in A will think "Hmm, due to length contraction, the rate at which he gets hit by photons is smaller than mine"

Person B will think the same way.

Person C in the observer frame will think that both ships will get hit at the same rate.

How do you resolve this contradiction?
 
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simpleton said:
Hi,

I was reading on special relativity and was trying to understand it. However, I am still not very sure about the concepts. For example, I have this problem:

I have 2 spaceships, A and B, traveling towards each other. Both have rest length x and speed v, where v is near the speed of light. Both are getting bombarded by photons that travel perpendicular to the direction of the spaceships.

The person in A will think "Hmm, due to length contraction, the rate at which he gets hit by photons is smaller than mine"

Person B will think the same way.

Person C in the observer frame will think that both ships will get hit at the same rate.

How do you resolve this contradiction?

There is no contradiction, all three statements are correct.
 
What I mean is, say person A and person B note down the number of photons that hit them. When they compare their readings, will they differ? And if they do, who got hit more times?
 
You need to specify the times at which they should start counting and stop counting.

If A says "I got hit by n photons between 12:00 and 12:01 on my clock", then B would say exactly the same. What you seem to be overlooking is that the events where A's clock change to 12:00 and to 12:01 are not one minute apart in B's frame.
 
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