Question

https://docs.google.com/viewer?a=v&q=cache:1B_T5M3FLNgJ:www.cpo.com/IPCRES/pdfs/unit1/ch2revques.pdf+&hl=en&gl=us&pid=bl&srcid=ADGEESgGQ-Ie-GunGkKXg7m279xlv5zRnaTbyEomTXO4xiF_rqwgIExKkEY3pSpUiLExzaK5j0-l4VF7whRGWgzLaMk9psGCDuk9XJISstUqilZihm-_l7ylLU3IiS0BzNiR-SwS4B9Q&sig=AHIEtbQyCyqqiQ24xRPYYicwbvMF7HyAqA - go to page 41 & #5. #help

Answer 1

The average acceleration is 200cm/s^2

Answer 2

and how did you find it?:)

Answer 3

Acceleration is the rate of change of velocity. The velocity changes by 100cm/sec in 0.5sec, so average acceleration is 200cm/sec^2

Answer 4

Okay! Thank you! :) & if you go to page 42 (same link) can you look at #'s 9, 12 & 13? :)

Answer 5

which bits dont you understand?

Answer 6

what do you mean?

Answer 7

have you attempted the questions you just asked me to do?

Answer 8

yes i didd. i reread them past 10 minutes, and still confused. physics is just not my subject.

Answer 9

Okay, for #9, we know speed = distance / time, so what does the gradient of each line represent?

Answer 10

the distance?

Answer 11

not quite. the gradient is how steep the line is, or distance / time, so it is the speed.
If the slope is steeper than another, does that mean the speed is higher or lower?

Answer 12

higher.

Answer 13

Great. So now you know that, you can work out which line is fastest and complete the question.

Answer 14

so it's 1, 2, 4, 3?

Answer 15

2 is steeper than 1, so it goes 2, 1, 4, 3 with 2 being the fastest

Answer 16

Okay! Thank you! & #10? (:

Answer 17

time = distance / speed

Answer 18

Oops, I meant 12:/

Answer 19

Take each segment at a time, remembering what we just learnt. Given each segment, if the gradient is constant, what does that tell us about the speed?

Answer 20

it's not changing.

Answer 21

Yes, well done. With this information, you can straight away rule out C and F. Have a go at finding the correct ones.

Answer 22

okay, so #1 is E ?

Answer 23

Yep

Answer 24

2 is b?

Answer 25

Yes

Answer 26

And what about Problem 13? :)

Answer 27

whats the formula for speed?

Answer 28

speed = distance / time