Answer:
The astronaut is moving at a speed of 0.238 m/s in a direction opposite the direction of the water shot out.
Explanation:
We are given;
Mass of astronaut; m1 = 84 kg
Mass of water shoot out; m2 = 2 kg
Initial speed of astronaut; u1 = 0 m/s
Initial speed of water shoot out; u2 = 0 m/s
Final speed of shoot out; v2 = 10 m/s
From law of conservation of momentum, we can say that;
Initial momentum = final momentum
Thus;
m1•u1 + m2•u2 = m1•v1 + m2•v2
Where v1 is the final speed of the astronaut
Plugging in the relevant values, we get;
(84 × 0) + (2 × 0) = (84 × v1) + (2 × 10)
0 = 84v1 + 20
-20 = 84v1
v1 = -20/84
v1 = -0.238 m/s
The negative sign indicates that the astronaut is moving 0.238 m/s in a direction opposite the direction of the water shot out.
