Question

for missmysteriously...

Answer 1

a particle is constrained to move along a straight line through O.
it starts initially at D, which is a fixed distance from O in the positive direction&moves at a constant velocity of 4ms^-1 for 15 sec. until; it is 100m from O for a furhter 25 sec, after which it travels in the opposite direction for 20 sec.
the total distance is 180m.

how do i draw a velocity–time graph?
and what is the final displacement of the particle from its initial position?

Answer 2

thats all the info

Answer 3

i posted it a few times but no one seems to answer because too many questions are and were posted at the same time :(

Answer 4

i dunno if you need a graph for that... have you done any other questions like this?

Answer 5

it says that i need a graph, its part of the question

Answer 6

http://monmouth.monmoodle.co.uk//file.php?file=%2F187%2FMEI%20A-LEVEL%20HOMEWORK%20RESOURCES%2FM1%2FM1%20Chapter%20Assessments%2FCA%20Motion%20Chapter%20Assessment.pdf
question2
cause i seems to be confusing people :S

Answer 7

part d says draw a velocity time graph

Answer 8

oh ok
i thought they were your questions, separate to this
i have to log in to see that question that way...

Answer 9

post a picture of the question?
just below this box, you can attach a file?

Answer 10

I don't understand.

Answer 11

hm

Answer 12

What is hm?

Answer 13

thinking

Answer 14

i kno it looks a bit weird cause its being copied and pasted from a pdf file

Answer 15

oh ok, so you have to have negative velocity on your graph

Answer 16

???
how do you know that theres a negative velocity?

Answer 17

i only drew a horizontal line at yaxis 4 at 15 seconds, and dunno how to draw the rest of it

Answer 18

ok

Answer 19

did you give up on me?

Answer 20

no sorry my pc went funny

Answer 21

it does that when it gets late, its like its getting tired or something :p
then when it does that openstudy wont let me go onto stuff :S

Answer 22

+ who am i to give up on you XD

Answer 23

A particle is constrained to move along a straight line through O. It starts initially at D, which is a fixed distance from O in the positive direction and moves at a constant velocity of 4 ms-1 for 15 seconds until it is 100 m from O. It remains 100 m from O for a further 25 seconds, after which it travels in the opposite direction for 20 seconds. The total distance travelled is 180 m. (i) Draw a distance-time graph to represent this situation. [4] (ii) What is the velocity in the final stage of the journey? [2] (iii) How far from O does the particle stop? [1] (iv) Draw a velocity–time graph. [4] (v) What is the final displacement of the particle? [2]

ill just give you the benefit of the my doubt, and explain the whole question here :)

so with that graph we drew we saw that a particle travels away from a point O for 15 seconds, at 4m/s making 60m travelled, so the particle travelled 60 metres, and was already 40 metres from the point O at the start of the question...

making it stop at 100m from point O just like was said at this bit : "... until it is 100 m from O"

Note, you should explain this when you write your answer, because the question is a bit tricky.

(iv) Draw a velocity–time graph - we did this on twiddla, im going to assume you can do it again :)
just remember when the particle " after which it travels in the opposite direction for 20 seconds" means negative velocity, travelled 80 metres, and in 20 seconds, so 80/20 = 4m/s but negative velocity so -4m/s

and for (v)What is the final displacement of the particle?
means, compared to where it started, and where it finished, what is the total distance
so you go 60-80 because it travelled 60 metres, then -80 metres (because of the opposite direction) so the answer would be 20 metres, because displacement is an absolute value (only positive) - you can see a picture that explains it in way mroe detail here: http://en.wikipedia.org/wiki/Displacement_(vector)

Answer 24

just tell me when that doesnt make sense.... cause im still here. thanks for not giving up :)

Answer 25

THANK YOU!!!!!!!!!!!!!
i understand it :)

+i should be the one saying that, cause im not very bright and people give up on me cause they cant be bother to explain it to me

Answer 26

shame i cant give you a medal :(

Answer 27

you must have some brains... i mean you understood my explanation... which doesn't usually happen.

Answer 28

+ you can explain things in detail in a way i can actually understand it :)
so happy now.
homework finished
yay!

Answer 29

im gonna go now
coz it bedtime :p
night!

Answer 30

gnight