Question

Камень брошен с высоты 10 м вертикально вверх с начальной скоростью 5м/с. найдите скорость при ударе камня о землю

Answer 1

Высота подъема

h=(v^2-v0^2/-2g

h=(0-25)/-20=1,25 м

Тело падает с высоты Н=h+H0=10+1,25=11,25м

Без начальной скорости

H=V^2/2g

V^2=2gH=2×10×11,25=225 извлекаем корень

V=15м/с Ответ

Answer 2

Problem Analysis

We are given the following information: - The stone is thrown vertically upwards from a height of 10 m. - The initial velocity of the stone is 5 m/s.

We need to find the velocity of the stone when it hits the ground.

Solution

To solve this problem, we can use the equations of motion for vertical motion under constant acceleration.

The equation that relates the final velocity (v), initial velocity (u), acceleration (a), and displacement (s) is:

v^2 = u^2 + 2as In this case, the stone is thrown vertically upwards, so the acceleration due to gravity (g) will act in the opposite direction to the motion of the stone. Therefore, the acceleration (a) will be equal to -g.

We can rewrite equation as:

v^2 = u^2 - 2gs where s is the displacement of the stone, which is equal to the initial height (h) of 10 m.

Substituting the given values into equation we have:

v^2 = (5 m/s)^2 - 2 * (-9.8 m/s^2) * 10 m Simplifying equation we get:

v^2 = 25 m^2/s^2 + 196 m^2/s^2 v^2 = 221 m^2/s^2 Taking the square root of both sides of equation we find:

v = √(221) m/s Therefore, the velocity of the stone when it hits the ground is approximately 14.87 m/s.

Answer

The velocity of the stone when it hits the ground is approximately 14.87 m/s.