The law of conservation of momentum states that the total momentum of interacting objects does not <u>change</u>. This means the total momentum <u>before</u><u> </u>a collision or explosion is equal to the total momentum <u>after</u><u> </u>a collision or explosion.
The easiest way to get a fairly accurate measure of your water flow rate is to time yourself filling up a bucket. So for example if you fill up a 10 litre bucket in 1.5 minutes, then your flow rate will be: 10/1.5 = 6.66 Litres per minute.
I don’t think we can answer this question with the information given. ANY ball thrown with ANY initial velocity v will be observed at a height h twice and with a time interval Δt.
