Similarly, the concept of kinetic energy can only be meaningful if its direction is specified. If that does not make it a vector, then please let me know what I can call it, and I'll oblige.
Absolutely not.
A
vector by definition is that which has both a
magnitude and a
direction.
A
scalar by definition is that which has only a
magnitude.
Kinetic energy is a scalar because the V^2 in the definition thereof is defined as the scalar product of the velocity with itself i.e., V.V, and is a scalar.
Kinetic energy is the energy an object possesses by virtue of its motion.
Or alternatively, the change in kinetic energy of an object is equal to the work done by a conservative force.
So kinetic energy and work must have the same units and type.
Work is the scalar product of force and displacement.
Force and displacement are vectors, and the scalar product of two vectors is a scalar.
But I'm confused...
The aircraft knows nothing about what the earth below it is doing. It doesn't need to, as
Wizofoz suggests.
Whether it touches down at a GS of 0kts or 70kts, as long as the IAS/TAS is the appropriate one, what is the problem?
I've touched down in a light 737 at a GS of <90kts on a day when it was gusting 65kts. I didn't even think about GS. The only thing I seek to preserve on finals is IAS. If I fly through a shear, I need to regain
IAS surely, not
GS?
What am I missing?