Find the fractional decrease of kinetic energy of a of mass m when a head on elastic collision takes place with another particle of mass m2 initially at rest. in this context show why hydrogen would be best to be used for slowing down. actually d20, not h, o is used. why?

In the image, the arrow is pointing to a celestial object. which attribute disqualifies the object from being a planet?

What is the rate of 12 liters of water moving through a water hose in 4.0 minutes?

Water is siphoned from a large tank and discharges into the atmosphere through a 50-mm diameter tube. the end of the tube is b = 2.1 m below the tank bottom which is a = 7.4 m deep, and viscous effects are negligible. determine the maximum height h over which the water can be siphoned without cavitation occurring. atmospheric pressure is 101.4 kpa, and the water vapor pressure is 1.79 kpa (absolute)