Final answer:
Speed adjustments in terms of knots are expressed in increments of 1, 2, 3, or 4 knots, with a knot being equal to 1 nautical mile per hour. Velocity vectors considered equal must have both the same magnitude and direction. Instantaneous speed is the speed of a vehicle at any given moment, as shown on a speedometer.
Step-by-step explanation:
When addressing how to express speed adjustments in terms of knots based on indicated airspeed (IAS), the appropriate increment options can vary. Typically, these adjustments are minor and precise, so options are given in increments of 1, 2, 3, or 4. The term 'knot' refers to a unit of speed equal to one nautical mile per hour. Hence, a 1-knot increment is a change of 1 nautical mile per hour in speed.
In each of the given situations:
- (a) Alice and Bob have velocity vectors that are not equal because although they have the same magnitude, they are moving in different directions (north vs west).
- (b) Alice and Bob's velocity vectors are not equal as they are moving in the same direction (west) but at different speeds.
- (c) Again, Alice and Bob have different velocity vectors due to different directions and magnitudes.
- (d) Alice and Bob's velocity vectors are not equal—they have the same speed but are moving in opposite diagonal directions.
- (e) Alice and Bob's velocity vectors are equal—they move at the same speed and in the same direction (northeast).
It is crucial to note that a vehicle, like a car, may have variable speed over time but its instantaneous speed is defined as its speed at a specific instant, which can be seen on a speedometer.