Answer:
Vp = 1 [m/s]
Step-by-step explanation:
In order to solve this problem, we must use the principle of conservation of the amount of movement. In the same way, analyze the before and after of the actions.
The moment before
The 50kg person is still hold (no movement) with the 2kg helmet
The moment after
The helmet moves at 25[m/s] in one direction, the person moves in the opposite direction, due to the launch of the helmet.
In this way we can apply the principle of conservation of movement, expressing the before and after. To the left we have the before and to the right of the equal sign we have the after.
Σm*V1 = Σm*V
where:
m = total mass = (2 + 50) = 52[kg]
V1 = velocity before the lunch = 0
(50 + 2)*V1 = (25*2) - (Vp*50)
0 = 50 - 50*Vp
50 = 50*Vp
Vp = 1 [m/s]