Respuesta :
Answer:
y = 2,645 10⁴ / m²
m=80 kg, y = 4.13 m
Explanation:
We must solve this problem in two parts, one when it is in free fall and another for the collision with the floor
Let's start by analyzing the crash with the floor,
Initial instant When it arrives but if you start to stop
p₀ = m v
Final moment. When he stopped
[tex]p_{f}[/tex] = 0
The momentum is related to the moment by
I = Δp = p_{f} –p₀
F t = 0 - mv
v = -F t / m
Let's calculate
v = -18000 0.040 / m
v = -720 / m
The sign indicates that the speed goes down
Now we use energy conservation at two points
Lowest point. Just before crashing
Em₀ = K = ½ m v²
Highest point. From where it began to fall
Em_{f} = U = m g y
Energy is conserved in the fall
Em₀ = Em_{f}
½ m v² = m g y
y = ½ v² / g
y = ½ (720 / m)² /9.8
y = 2,645 10⁴ / m²
For an explicit height value, the object's mass must be known, suppose the masses are m = 80 kg
y = 2,645 10⁴/80²
y = 4.13 m
