It's a physical change. the water is changing it's physical state
I disagree with that opinion, and I have solid Physics to back me up.
The forces of gravity are always equal in both directions. The sun pulls the Earth with exactly the same force with which the Earth pulls the sun.
It may seem weird, but your weight on Earth is exactly the same as the Earth's weight on you. For the same reason.
Answer:
v_f = 10.85 m/s
Explanation:
We will apply the law of conservation of momentum here:

where,
m₁ = mass of roller skater = 47 kg
m₂ = mass of bag = 6 kg
v_1i = initial speed of roller skater = 12 m/s
v_2i = initial speed of the bag = 0 m/s
v_1f = final speed of the roller skater = ?
v_2f = final speed of the bag = ?
Both the bag and the skater will have same speed at the end because kater is carrying the bag:
v_1f = v_2f = v_f
Therefore, the equation will become:

<u>v_f = 10.85 m/s</u>