Question

Notice that the speed halfway down is not half the final speed. Another interesting point is that the final answer doesn't depend on the mass. That is really a consequence of neglecting the change in kinetic energy of Earth, which is valid when the mass of the object, the diver in this case, is much smaller than the mass of Earth. In reality, Earth also falls towards the diver, reducing the final speed, but the reduction is so minuscule it could never be measured. QUESTION Qualitatively, how will the answers change if the diver takes a running dive off the end of the board

Answer 1

its speed is insignificant before the diver's speed change, so the result does not change

Step-by-step explanation:

In this exercise of conservation of the momentum, the system is formed by the diver and the Earth

initial instant (before jumping)

p₀ = 0

final instant (after jumping)

`p_(f)` = m v + M v²

how momentum is conserved

p₀ = p_{f}

0 = m v + M v²

v² = m / M v

since the mass of the Earth is M = 10²⁴ kg

its speed is insignificant before the diver's speed change, so the result does not change