# maths --plse help me..

The pilot of an aircraft flying horizontally at a speed of 1200 Km/hr observes an angle of depression of a point on the ground changes from 30 degree to 45 degree in 15 seconds. Find the height of the aircraft at which it is flying?

1. 👍
2. 👎
3. 👁
1. at 1200km/hr, the plane travels

1200km/hr * 15sec * hr/3600sec = 5km

If the height of the plane is h, and the horizontal distance of the plane from the point on the ground after the 2nd observation is x,

h/x = tan 45° = 1
h/(x+5) = tan 30° = 1/√3

h=x, so,
h/(h+5) = 1/√3
h = 5/(√3-1) = 6.83 km

1. 👍
2. 👎
2. 6.83

1. 👍
2. 👎

## Similar Questions

1. ### math

A plane takes off at an angle of 20 degrees. Assuming a constant speed and trajectory, by the time it has travelled 25 kilometres horizontally, how high will it be flying?

2. ### physics

a jet pilot takes his aircraft in a vertical loop. a) if the jet is moving at a speed of 2000 km/h at the lowest point of the loop, determine the minimum radius of the circle so that the centripetal acceleration at the lowest

3. ### Algebra

A pilot flew a 400-mile flight in 2.5 hours flying into the wind. Flying the same rate and with the same wind speed, the return trip took only 2 hours, with a tailwind. What was the speed of the wind?

4. ### trigonometry

the pilot in an airplane observes the angle of depression of a light directly below his line of sight to be 30.4 degrees. a minute later, its angle of depression is 43.0 degrees. if he is flying horizontally in a straight course

1. ### Physics

A cargo plane is flying horizontally at an altitude of 10000m with a velocity of 800km/h when a cargo pallet falls out the back ramp. (i) How long does it take to fall to the ground? (ii) How far horizontally is the pallet from

2. ### science

A general aviation aircraft, with a wing surface area of 18 square metres, flies at sea level with a speed of 180 kilometres per hour. Its lift curve is shown below. Given that lift equals weight for this aircraft and that the

3. ### physics

two aircraft P & Q are flying at the same speed, 300m/s.The direction along which P is flying is at right angle to the direction along which Q is flying. find the magnitude of the velocity of the aircraft P relative to aircraft Q?

4. ### Physics

The pilot of an aircraft wishes to fly due west in a 50.0 km/h wind blowing toward the south. The speed of the aircraft in the absence of a wind is 228 km/h. a) How many degrees from west should the aircraft head? Let clockwise be

1. ### Physics

A pilot flying low and slow drops a weight; it takes 2.8 s to hit the ground, during which it travels a horizontal distance of 100 m . Now the pilot does a run at the same height but twice the speed. How much time does it take the

2. ### Maths

An aeroplane is flying horizontally directly towards the city at an altitude of 400 metres. At a given time the pilot views the city lights of Melbourne at an angle of depression of 1.5 degrees. Two minutes later the angle of

3. ### Maths

A plane is flying at an altitude of 880 m. Sarah is standing on the ground and she observes the angle of elevation to the plane as 67'40'. Twenty-five seconds later the angle of elevation had changed to 24'30'. (a) How far has the

4. ### Physics

At a particular instant, a stationary observer on the ground sees a package falling from a moving airplane with a speed vobserver at an angle θ to the vertical. To the pilot flying horizontally at a constant speed relative to the