Question

ОЧЕНЬ НУЖНО! 80 БАЛЛОВ!!! Θ_Θ Незрелый плод персика массой 190 г падает с дерева. Чему равна кинетическая энергия персика за миг до удара о землю, если персик свободно падал с высоты 1,4 м? С какой скоростью персик врежется в землю? (Принять g=9.8 Нкг). Ответ (округли до десятых): υ≈ м/сEк≈ Дж???

Answer 1

Ответ:

Объяснение:

m=0.19 кг             |    1)   Ek=En=m*g*h=0.19*9.8*1.4=2.6Дж

 h=1.4 м                |     2)Ek=$\frac{m*v^{2} }{2}$

--------------------------    3)v=$\sqrt{2*g*h}$=$\sqrt{2*9.8*1.4}$)≈5,2м/с

Ek=?   v=?

                   

Answer 2

Calculation of Kinetic Energy:

To calculate the kinetic energy of the peach before it hits the ground, we can use the formula for kinetic energy:

Kinetic Energy (KE) = 1/2 * mass * velocity^2

Given: - Mass of the peach (m) = 190 g = 0.19 kg - Height from which the peach falls (h) = 1.4 m - Acceleration due to gravity (g) = 9.8 m/s^2

First, let's calculate the velocity of the peach just before it hits the ground using the equation of motion:

v^2 = u^2 + 2gh

Where: - u = initial velocity (which is 0 since the peach is freely falling) - g = acceleration due to gravity - h = height from which the peach falls

Substituting the given values:

v^2 = 0 + 2 * 9.8 * 1.4

v^2 = 27.44

Taking the square root of both sides:

v ≈ 5.24 m/s (rounded to two decimal places) [[1]]

Now, we can calculate the kinetic energy of the peach using the formula mentioned earlier:

KE = 1/2 * m * v^2

Substituting the given values:

KE ≈ 1/2 * 0.19 * (5.24)^2

KE ≈ 1/2 * 0.19 * 27.44

KE ≈ 2.61 J (rounded to two decimal places) [[1]]

Therefore, the kinetic energy of the peach just before it hits the ground is approximately 2.61 Joules.

Calculation of Impact Velocity:

The impact velocity of the peach when it hits the ground can be calculated using the equation of motion mentioned earlier:

v^2 = u^2 + 2gh

Where: - u = initial velocity (which is 0 since the peach is freely falling) - g = acceleration due to gravity - h = height from which the peach falls

Substituting the given values:

v^2 = 0 + 2 * 9.8 * 1.4

v^2 = 27.44

Taking the square root of both sides:

v ≈ 5.24 m/s (rounded to two decimal places) [[1]]

Therefore, the impact velocity of the peach when it hits the ground is approximately 5.24 m/s.

Note: The impact velocity is the same as the velocity just before hitting the ground since there is no air resistance.