(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A plane flying at a constant velocity v (parallel to x-axis) at a height h = 8 km is being tracked by a radar located at origin. if the angle A is decreasing at the rate of 0.025 rad/s, the velocity of the plane when A = 60 degrees is: (A is the angle made by the position vector of plane with the x-axis)

a) 1440 km/h

b) 960 km/h

c) 1920 km/h

d) 480 m/h

2. Relevant equations

vt = h cot A

differentiating w.r.t t (time):

v = h cosec^{2}A (0.025) -------eqn 1

= 0.27 km/h

3. The attempt at a solution

the answer is nowhere near what one would expect. also, if v is consatant then how can it depend on A? (eqn 1) Where am i going wrong?

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# Homework Help: To find speed of a plane when position of radar is given

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