Question

The compass needle of the airplane shows it is heading due North and speedmeter indicates a velocity 240 kmh^-1. Wind is blowing 100 kmh^-1 due east. Find the velocity of airplane with respect to earth.

• A. 260 ms^-1, 23⁰ E of N
• B. 260 ms^-1, 23⁰ W of N
• C. 260 ms^-1, 32⁰ E of N
• D. None

Answer 1

Answer: (A)

260 ms^-1, 23⁰ E of N

Answer 2

v_AE = 100$\widehat{i}$ + 240$\widehat{j}$

v_AE = $\sqrt{(240)^{2} + 100^{2}} = 260ms^{- 1}$;

φ = tan^-1(100/240) = 23⁰ E of N.