How to solve this problem? Using derivative knowledge to solve the difficulties in the detailed process. Thank you.

Let the elevation angle be a, then BC=h/(tana), where h is 2km.

Both sid

How to solve this problem? Using derivative knowledge to solve the difficulties in the detailed process. Thank you.

Let the elevation angle be a, then BC=h/(tana), where h is 2km.

Both sides of the above formula take the derivative of t, d(BC)/dt=d(h/tana)/dt,

According to the definition of speed, d(BC)/dt is the reciprocal of the aircraft speed, so there is -v=(-h/(sina)2)(da/dt), where da/dt is the angular velocity of the camera lens rotation.

When the plane passes over the target, a=90 degrees. Replace the units of v and h with m/s and m, and substitute them for calculation. Da/dt= 1/36, which is about 1.59 degrees per second.

If you don't understand anything, just ask.

Da/dt is the angular velocity, 1/36 radians/second.