Angular velocity in a uniform circular motion.

tete9000
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Hi people, i had my final exam yesterday, and one of the questions was this "a particle in uniform circular motion, moved for an interval of 0.185 seconds in a circular path of radius 16 cm, what is the angular velocity of the particle"?
I think that the question lacks information, am i right?We all know that "s = rϑ", and that "v = s/t", "v = rω", I made the substitutions needed, but came with the result that there's a lack of information, so please people, help is needed.
 
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Welcome to PF!

Hi tete9000! Welcome to PF! :smile:
tete9000 said:
"a particle moving in a uniform circular motion, moved for a period of 0.185 seconds in a circle of radius 16 cm, what is the angular velocity of the particle"?

I agree, that's very badly worded.

(was it in English, or is that a translation?)

If I was taking the exam, I would assume that the question meant that "in a circle" meant a complete circle; alternatively, that "period" was being used in its technical sense rather than its general sense, as if it had said "with a period" (and so again meant the time to make a complete circle).

But that's not what the question says. :frown:
 


Sorry tiny-tim, i edited the question concerning the points you mentioned, but you agree that there's a lack of information relating the question, right?
 
Hi tete9000! :smile:

(just got up :zzz: … )
tete9000 said:
"a particle in uniform circular motion, moved for an interval of 0.185 seconds in a circular path of radius 16 cm, what is the angular velocity of the particle"?
tete9000 said:
Sorry tiny-tim, i edited the question concerning the points you mentioned, but you agree that there's a lack of information relating the question, right?

Yes.

(I'd still assume it meant a complete circle, but on the new wording, that's just a wild guess :redface:)
 
tete9000 said:
Hi people, i had my final exam yesterday, and one of the questions was this "a particle in uniform circular motion, moved for an interval of 0.185 seconds in a circular path of radius 16 cm, what is the angular velocity of the particle"?



I think that the question lacks information, am i right?


We all know that "s = rϑ", and that "v = s/t", "v = rω", I made the substitutions needed, but came with the result that there's a lack of information, so please people, help is needed.

There must be something lacking. If it had said "the particle completed a full circle at t=0.185, taking into account that the motion started at t=0", then nothing would have sounded defective.

AB
 
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