The helicopter steadily descends vertically downward at a speed of 10 m / s. When the helicopter was at an altitude

The helicopter steadily descends vertically downward at a speed of 10 m / s. When the helicopter was at an altitude of 120 meters above the ground, an object was dropped from it. In how many seconds the object will fall to the ground. Do not take into account air resistance.

The initial speed of an object falling and dropped from a helicopter is equal to the speed of descent of the latter, i.e. v = 10 m / s.

The path of the falling body: S = v * t + g * t² / 2.

According to the task data, we get:

4.9 * t² + 10 * t = 120,

4.9 * t² + 10 * t – 120 = 0.

Solving this quadratic equation, we get:

t ≈ 4.03 s.

Answer: the item will fall in 4.03 seconds after being dropped from a helicopter.