Timeline for If the velocity of particle $A$ exceeds that of $B$, is the acceleration of $A$ greater than $B$?
Current License: CC BY-SA 3.0
15 events
| when toggle format | what | by | license | comment | |
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| Sep 13, 2013 at 5:05 | vote | accept | Gerard | ||
| S Aug 25, 2013 at 12:34 | history | suggested | Rob | CC BY-SA 3.0 |
Clarified the problem's assumptions
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| Aug 25, 2013 at 12:22 | review | Suggested edits | |||
| S Aug 25, 2013 at 12:34 | |||||
| Aug 25, 2013 at 8:32 | answer | added | joshphysics | timeline score: 6 | |
| Aug 25, 2013 at 7:57 | comment | added | wataya | So the problem does not assume that initally A's velocity was lower than B's. So my first comment applies and the answer is 'no'. | |
| Aug 25, 2013 at 7:08 | comment | added | Gerard | The exact wording of the question is "Two cars are moving in the same direction in parallel lanes along a highway. At some instant the velocity of car A exceeds the velocity of car B. Does this mean that the acceleration of car A is greater than that of car B?" | |
| Aug 25, 2013 at 7:05 | history | edited | Gerard | CC BY-SA 3.0 |
added 61 characters in body; edited tags
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| Aug 25, 2013 at 7:00 | comment | added | wataya | OK. I don't have that textbook. If the v-t line of A crosses that of B from below, then necessarily at that point A's velocity has to be greater than that of B. Since it's assumed to be constant that's your answer. If your textbook says otherwise, carefully check whether the formulation of the problem leaves a loop-hole for the crossing to be from above. | |
| Aug 25, 2013 at 6:59 | comment | added | David Z | @Gerard you should edit the question to mention that, then. (Probably also add the homework tag while you're at it) | |
| Aug 25, 2013 at 6:46 | comment | added | Gerard | Acceleration of both particles is assumed to be constant. If you are unclear about the question: This is question 13 from Chapter 2 Resnick Halliday Physics. | |
| Aug 25, 2013 at 6:33 | comment | added | wataya | Are you talking about average or momentary accelerations? | |
| Aug 25, 2013 at 6:26 | comment | added | wataya | You should make that clear. The origin is also some point. | |
| Aug 25, 2013 at 6:24 | comment | added | Gerard | No. The question says that *at some point$ A's velocity exceeds B's. It wasn't higher to begin with. | |
| Aug 25, 2013 at 6:15 | comment | added | wataya | Not sure if I understand your question correctly. If A starts with a high velocity and travels at constant speed and B starts from rest and is accelerated, than obviously A's velocity is greater than that of B and B's acceleration (>0) exceeds that of A (=0). | |
| Aug 25, 2013 at 5:16 | history | asked | Gerard | CC BY-SA 3.0 |