Forces in a Climb -Vectors
- Using the first
equation: L cos (c) + F sin (c) -D sin (c) - W = ma (vertical)
and the third equation: F -D = Fex , explain and show how
the fourth equation: L cos (c) + Fex sin (c) - W = ma (vertical).
Factor sin (c) out of last two terms and
for (F - D).
- Using the second
equation and the third equation, explain and show how to obtain the
In the second equation, factor cos (c)
out of the first and third terms and substitute as in above.
- Why isn't
W multiplied by a sine or cosine?
Weight is a downward force, so it would
be W sin (90) or just W. (sin 90 is 1).
- Using the given
diagram, theorems/postulates of geometry, and vectors, explain each
term in the first two equations.
= F sin 10 positive (upward) vertical
= L cos 10 positive vertical
1 + angle 2 = 90 Lift is perpendicular (vertical) to flight
1 + angle 3 = 90 Acute angles of a right triangle are complementary.
angle 1 + angle 2 = angle 1 + angle 3
angle 2 = angle 3
angle 2 = 10 then angle 3 must also.
= D sin 10 negative (downward) vertical
= F cos 10 Positive (forward)
= L sin 10 Negative (backward)
= D cos 10 Negative (backward)
only affects the vertical, not horizontal, or W cos 90 = 0