Please help with these motion questions (1 Viewer)

kpad5991

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Hi I have completed the entire chapter in motion but I’m struggling with the following questions they are marked with the dots.

https://imgur.com/gallery/EEgH9

But listing the questions
10c
13b,e
16d, e
10b,c,d
13a,b,c
14d
17b

Can some kind soul please help if you want to see any solutions let me know
 

Drongoski

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Doing a tiny part to set the ball rolling.

Q10c: change of displacement means change in position(value of x): car started at x = 8m and ended up at x = 8m: so no change. So change in displacement is 0m. Therefore avg change in velocity = 0m/30 sec = 0 m/sec.
 

HeroWise

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"Doing a tiny part to set the ball rolling."

Is it in respect to Awesomeness ahaha? dx/dA where A measures Drongos Awesomeness!




EDIT: Any specifics which are hard?
 
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Drongoski

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Q17b

acceleration a = -2cos t is positive if -2cos t > 0
i.e. if cos t < 0
Now cos t is < 0 for pi/2 < t < 3pi/2 (if you are familiar with the graph of y = cos t)and again and again later every 2 pi secs later.


For Q14, if you can do parts a, b and c, you are already doing very well.

For Q14d: 1st 4 secs, particle moves 32m to the right. 4 secs later it reverses direction (moving left) and returns to its original position, travelling another 32m. 2 secs later, it moves another 40m to the left. Therefore in the 10 secs, particle has travelled 32m + 32m + 40m = 104m. .: avg speed = 104m/10 sec = 10.4m/sec. (its position at t = 10 sec is x = -40m, i.e. its displacement is -40m)



I think many of these questions are rather difficult for students of 2U Maths. Problem is not that the area is all that difficult. Problem I think is, even before you do the questions, most people do not have a good idea of basic and simple concepts of distance, displacement, velocity and speed. You also need to know basic differentiation and integration.

I don't know how you have been taught. I would just love to stand before a class to make all these ideas clear, before you embark on working on the exercises on motion.
 
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kpad5991

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Can someone please help with 13b I got i but how is the distance 600m during the next 30 seconds
 

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