00:01
All right, so let's say we have an aircraft that kind of sort of looks like this.
00:04
And we're told the lift force goes in this direction, and it makes a 22 degree angle with the vertical.
00:11
And we're told that the lift force has a magnitude, we'll call it fl, 2 .12 million newtons.
00:22
And so we, or i guess they call it l.
00:24
So we'll write it as l.
00:26
And then from this information, we want to find the mass of the plane.
00:29
So what we know is that the vertical component of our lift force, which is l times the cosine of this angle, should be equal to the weight.
00:37
So because the centripetal force points this way, that's the direction of our net force.
00:43
So that means the weight has to equal the vertical component of this.
00:47
So we have mg equals l cosine theta.
00:50
So that gives us a mass 2 .12 times 10 of the 6 times the cosine of 22, divided by 9 .8...