The rate of flow of electric CHARGE past any point is described in the unit of electric CURRENT ... the Ampere.
Of the forces listed I think the force of him diving and sliding across the infield acted on the player.
I think so because the slowing down was a result of an action, and I don’t think that should count as An action when it is the result of an action. However, the act of diving head-first into second base and sliding across the infield are independent actions and will cause friction, which will act upon the player.
The true scientific way is the last: using the water displacement method
Answer:
P₂ = 138.88 10³ Pa
Explanation:
This is a problem of fluid mechanics, we must use the continuity and Bernoulli equation
Let's start by looking for the top speed
Q = A₁ v₁ = A₂ v₂
We will use index 1 for the lower part and index 2 for the upper part, let's look for the speed in the upper part (v2)
v₂ = A₁ / A₂ v₁
They indicate that A₂ = ½ A₁ and give the speed at the bottom (v₁ = 1.20 m/s)
v₂ = 2 1.20
v₂ = 2.40 m / s
Now let's write the Bernoulli equation
P₁ + ½ ρ v₁² + ρ g y₁ = P2 + ½ ρ v₂² + ρ g y₂
Let's clear the pressure at point 2
P₂ = P₁ + ½ ρ (v₁² - v₂²) + ρ g (y₁-y₂)
we put our reference system at the lowest point
y₁ - y₂ = -20 cm
Let's calculate
P₂ = 143 10³ + ½ 1000 (1.20² - 2.40²) + 1000 9.8 (-0.200)
P₂ = 143 103 - 2,160 103 - 1,960 103
P₂ = 138.88 10³ Pa
Answer: zero.
Justification:
The downward velocity of the sky diver just before starting to fall is zero, assuming that the helicopter is not moving but just hovering.
Before starting to fall, the velocity of the skydiver is the same of the helicopter, which is zero. It is only, once she jumps out of the helicopter that her weight is not supported by the helicopter and so the gravitational force of the Earth attracts the skydiver and she starts to gain velocity at a rate equal to g (around 9.81 m/s²).
