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# Balanced forces query watch

1. Hi please could someone explain to me why the answer can't be 'it will be stationary' as well as 'it will have a constant speed'
Thanks!
2. (Original post by razzy02)

Hi please could someone explain to me why the answer can't be 'it will be stationary' as well as 'it will have a constant speed'
Thanks!
You can only tick one box, and the choice comes down to one of the two you've mentioned. A "constant speed" allows for the possibility that speed is zero, i.e. stationary. But you don't know that the car is stationary.
3. as Ghostwalker says, the option "stationary" is part of the option "constant speed" but not the other way round.
4. (Original post by ghostwalker)
You can only tick one box, and the choice comes down to one of the two you've mentioned. A "constant speed" allows for the possibility that speed is zero, i.e. stationary. But you don't know that the car is stationary.
Thank you so much! So the answer will be constant speed?
5. (Original post by razzy02)
Thank you so much! So the answer will be constant speed?
That's correct.
6. (Original post by razzy02)

Hi please could someone explain to me why the answer can't be 'it will be stationary' as well as 'it will have a constant speed'
Thanks!
If you consider the physics of the situation, it's hard to see how the force acting opposite to the direction in which the car is spointing is likely to be anything other than drag. If the car were stationary, the drag would be zero, so there are good reasons for preferring the third option beyond it being more general. Of course, the question doesn't identify the source of the forces so it's possible that the car is stationary and has two big springs attached to it pulling in opposite directions by equal amounts but (wait for it) that's a bit of a stretch.
7. (Original post by astro67)
If you consider the physics of the situation, it's hard to see how the force acting opposite to the direction in which the car is spointing is likely to be anything other than drag. If the car were stationary, the drag would be zero, so there are good reasons for preferring the third option beyond it being more general. Of course, the question doesn't identify the source of the forces so it's possible that the car is stationary and has two big springs attached to it pulling in opposite directions by equal amounts but (wait for it) that's a bit of a stretch.
Haha! thank you so much for the reply, I appreciate it!

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