Section I - Multiple Choice (1 Viewer)

hjed

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Pretty sure 10 was B, positive acceleration = increasing speed. (although in this case it would have been decreasing velocity)
 

CM07

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Yes 10 was d since
a=+2
v=-3
va=-6 since negative therefore decelerating/decreasing speed
Also as v=-3 (negative) therefore at that time particle was moving left of origin
Jfc I didn't think and used acceleration as speed fml.

im pretty sure 10 was b

remember velocity = speed WITH direction

and -acceleration means negative/going down
so i think it's B
I don't even know anymore. Still hoping it's (B).
 
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Recondit

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Im not sure on this anymore...
where a=+2 it means acceleration is acting to the right of the origin but since the particle is moving left to the origin shown by v=-3, it translates to decelerating moving to the left
+ acceleration doesn't apply to accelerating left and right but only right if you get what I mean
 

joe_y

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drop kicks the answers are as follows;-

1. D
2. B
3. A
4. A
5. C
6. D
7. B
8. B
9. C
10. D

These are certain correct answer !!!!!!!!!!!!!!!!!
 

bedpotato

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I don't even know anymore. Still hoping it's (B).
If a > 0, the particle is travelling at an increasing speed.
If v < 0, the particle is travelling towards the left (or towards the origin).

For questions like: for what values of x is f(x) is increasing, isn't it when f'(x) > 0 ?

look at v as f(x) and a as f'(x)

Since a [f'(x)] is > 0, v [f(x)] is increasing. So the speed is increasing.

Therefore, the particle is moving towards the origin at an increasing rate (or speed, whatever it was).
 

Alex Griffiths

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Congrats faggot, you got question 6 wrong... so much for calling everyone a drop kick
 

Alex Griffiths

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^ To be honest, i freaked out when I saw the question, but realised that there was a much simpler way of finding the answer (I stared at it for a few minutes): substitute values into the equation! The answer (if i remember correctly) is A - Substituting in x=pi/2 (and the other values in the graph), you find that y=o, meaning the first one is correct.
 

Focus is Key

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^ To be honest, i freaked out when I saw the question, but realised that there was a much simpler way of finding the answer (I stared at it for a few minutes): substitute values into the equation! The answer (if i remember correctly) is A - Substituting in x=pi/2 (and the other values in the graph), you find that y=o, meaning the first one is correct.
Please dear god let this be true; this is what I did but everyone else was posting different answers so I got worried.
 
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Alex Griffiths

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^ To be honest, i freaked out when I saw the question, but realised that there was a much simpler way of finding the answer (I stared at it for a few minutes): substitute values into the equation! The answer (if i remember correctly) is A - Substituting in x=pi/2 (and the other values in the graph), you find that y=o, meaning the first one is correct.
Note: you must be in radians :p
 

hjed

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^ To be honest, i freaked out when I saw the question, but realised that there was a much simpler way of finding the answer (I stared at it for a few minutes): substitute values into the equation! The answer (if i remember correctly) is A - Substituting in x=pi/2 (and the other values in the graph), you find that y=o, meaning the first one is correct.
You remember incorrectly x=pi/2 is not on any of the graphs, but I get what you mean. If you know the formula it is much quicker to do it that way though
 

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