Question

Which of the following is false with respect to Earth centered inertial coordinate system?

(a) Accuracy is 10^-5/hr

(b) Newton’s laws are not valid

(c) Angular coordinates of stars are conventionally tabulated in ECI

(d) Used in mechanizing inertial navigators

I got this question during an online interview.

This intriguing question comes from Navigation Equations in division Introduction & Navigation Equations of Avionics

Answer 1

Correct choice is (b) Newton’s laws are not valid

Easy explanation: The Earth centered coordinate system has three navigational functions. First, Newton’s laws are valid in any ECI coordinate frame, Second, the angular coordinates of stars are conventionally tabulated in ECI. Third, they are used in mechanizing inertial navigators.