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net difference d/ t = ?

Quote from: Thebox on 22/02/2016 10:10:48net difference d/ t = ?you must have misunderstood the question, d/t is not a difference it is a speed if d is the distance (easily calculated using the speed of light).You need to go back and ask for clarification.PS - Net (or Nett in US) means a part of something, like Net income is income after deductions such as tax.

I have asked and he says, he was asking about the net difference between the two travelling bodies d/t

Quote from: Thebox on 22/02/2016 11:13:51I have asked and he says, he was asking about the net difference between the two travelling bodies d/tthere is no net difference the distance is the same, the speed is the same. If you want to consider these as vectors, you would define one as +ve and the other -ve, net difference 0.Always happy to help with homework questions by giving hints, but in this case I still don't understand the question.

A question of my own, why would you define -ve and +ve , is this to show the invert velocity?

what does the e mean?

and how would you express net difference in a symbol form?

Quote from: Thebox on 22/02/2016 12:06:41A question of my own, why would you define -ve and +ve , is this to show the invert velocity?No just direction.Quote from: Thebox on 22/02/2016 12:06:41what does the e mean?+ve is just shorthand for positive.Quote from: Thebox on 22/02/2016 12:06:41and how would you express net difference in a symbol form?Not aware of a symbol

d=x net difference t=0Explaining a back and forth journey?

Quote from: Thebox on 22/02/2016 12:15:34d=x net difference t=0Explaining a back and forth journey?No, how can t=0 if you went there and back?If you went there and back then d=2x and time =2t

OK, this confused me:"net difference d/ t = ?"

The important thing about the question is the realisation (following the experimental discovery) that c is constant regardless of direction, so A-> B = B->A in every respect. Obviously d = 300,000,000 km or thereabouts.

how would you express net difference in a symbol form?

Quote from: TheBoxhow would you express net difference in a symbol form?In mathematics, physics and chemistry, the Greek letter Delta ("d" sound) is often used to represent a difference:"Δ":Capital Delta"δ": lower case deltaSometimes the equivalent English letter "d" is used to represent a infinitesimal difference (as in velocity=^{dt}/_{dt})....and a "curvy d" () in more complicated scenarios.

Then maybe simply ^{dt}/_{dt}=0 net difference?

Quote from: Thebox on 23/02/2016 14:38:13Then maybe simply ^{dt}/_{dt}=0 net difference?no, ^{dt}/_{dt}=1 for a difference you have to subtract eg t_{1}-t_{2}=δt

Quote from: Colin2B on 23/02/2016 17:38:35Quote from: Thebox on 23/02/2016 14:38:13Then maybe simply ^{dt}/_{dt}=0 net difference?no, ^{dt}/_{dt}=1 for a difference you have to subtract eg t_{1}-t_{2}=δtIn my scenario t_{1}-t_{2}=o

You can't simply subtract t2 from t1. Both of the time intervals are in the same direction since time does not go backwards. You gain nothing from the operation. It would be different if the time component was part of a velocity calculation. As that has a well defined direction since it is a vector.

Quote from: Thebox on 23/02/2016 17:51:27Quote from: Colin2B on 23/02/2016 17:38:35Quote from: Thebox on 23/02/2016 14:38:13Then maybe simply ^{dt}/_{dt}=0 net difference?no, ^{dt}/_{dt}=1 for a difference you have to subtract eg t_{1}-t_{2}=δtIn my scenario t_{1}-t_{2}=oYou can't simply subtract t2 from t1. Both of the time intervals are in the same direction since time does not go backwards. You gain nothing from the operation. It would be different if the time component was part of a velocity calculation. As that has a well defined direction since it is a vector.

ok, just to be clear.If you travel from home to nearby town and it takes 1hr then return journey is also 1hr. Total journey time (round trip) is 2hr, but the difference between the 2 journey times is 0, in other words they are the same.Sorry to labour this but we've got to be clear to avoid misunderstandings