00:01
Here in this question it is given that the weight here equals to 3 ,000 lb.
00:08
The wing area equals to 181 feet square.
00:18
The aspect ratio equals to 6 .2.
00:26
The drag efficient equals to 0 .027.
00:37
Okay, the efficiency factor equals to 0 .91.
00:43
Okay.
00:45
Now we know that here the airplane is powered by a piston engine at 345 hp maximum at c level.
00:58
Okay.
01:00
Now here we can write that the power required at t level.
01:11
Okay.
01:12
Now for this we can write that a velocity v infinity equals to 100 feet per second.
01:23
Okay.
01:24
Now here we also know that our q infinity that equals to 1 .5.
01:29
That equals to 1 .2.
01:30
By 2 that is kinetic energy 1 by 2 p infinity v infinity whole square okay now here now here we can write that it will be it is q infinity okay now here it will be 1 by 2 it will be 0.
01:49
0 37 into 100 whole square okay so here after solving this we get a q infinity equals to 11 .89 lb by feet square.
02:07
Now we have our q infinity.
02:10
Now here we can write that a c l equals to it will be w by q0 d s.
02:22
Okay.
02:23
Here we know that a w is 3 ,000 lb.
02:26
Okay, we have calculated.
02:28
We know the q not is 11 .89.
02:31
Okay and our ds is 181 okay basically it's wing area okay now here we get our c l equals to 1 .39 okay now after we got a c l now we need to calculate our cd so cd equals to cd not plus c l whole square divided by pi a r okay now this is our area okay now here it will be equal to 0 .07 plus we have calculated that this is 1 .39 whole square okay it will be divided by pi into 0 .91 into 6 .2 okay 0 .91 into 6 .2 okay now it will become 0 .027 plus it will be 0 .109 so we get a cd equals to 0 .136.
03:31
Okay, so now we have got our cd.
03:35
Now let's calculate our tr.
03:38
Okay.
03:38
Now for tr here, we have w divided by cl divided by cd.
03:46
Okay, so we have 3 ,000.
03:47
It will be divided by 1 .39.
03:51
It will be divided by 0 .136.
03:55
Okay...