WEBVTT
1
00:00:01.040 --> 00:00:03.580 A:middle L:90%
it's clear someone named Reed here. So we're finding
2
00:00:03.580 --> 00:00:10.099 A:middle L:90%
the tire tire life and thousands so we'll get and
3
00:00:10.099 --> 00:00:19.949 A:middle L:90%
I could have 275 0.4 to 77 three piece square
4
00:00:21.440 --> 00:00:37.479 A:middle L:90%
plus 19,748 0.5 to 7. Five p minus 2.7
5
00:00:38.240 --> 00:00:47.810 A:middle L:90%
35 for part B. We're gonna use our equation
6
00:00:47.810 --> 00:00:52.130 A:middle L:90%
for l that we call it and differentiate it.
7
00:00:52.140 --> 00:00:56.429 A:middle L:90%
So I get d l over d p this sequel
8
00:00:56.429 --> 00:01:11.569 A:middle L:90%
to 0.55 through 896 p plus 19 0.748 5 to
9
00:01:11.579 --> 00:01:15.810 A:middle L:90%
8 to differentiate. I didn't use the equation above
10
00:01:15.010 --> 00:01:19.870 A:middle L:90%
. I used the equation known in thousands. So
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00:01:19.879 --> 00:01:33.359 A:middle L:90%
when P is equal to 30 yet approximately 3.22 and
12
00:01:33.359 --> 00:01:42.349 A:middle L:90%
when P is equal to 40 get approximately negative 2.286
13
00:01:44.939 --> 00:01:56.109 A:middle L:90%
and the unit are inches cubes per pound, and
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00:01:56.109 --> 00:01:59.430 A:middle L:90%
the derivative is the rate of change of life,
15
00:01:59.439 --> 00:02:01.980 A:middle L:90%
of tyre and respect to the pressure. And when
16
00:02:01.980 --> 00:02:06.680 A:middle L:90%
the derivative is positive, it means that, um
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00:02:06.680 --> 00:02:09.080 A:middle L:90%
, there's a further increase in pressure will increase the
18
00:02:09.080 --> 00:02:13.250 A:middle L:90%
life of the tire and for negative means that a
19
00:02:13.250 --> 00:02:15.300 A:middle L:90%
further increase in pressure will decrease the life of the
20
00:02:15.300 --> A:middle L:90%
tire