Are you referring to the fact that water is a compound while hydrogen is an element? If I'm wrong just comment and clarify and I can edit it, I don't even know what kind of unit you're in. :)
maximum allowed value of the speed in roller coaster is given as
now from kinematics we can say
here initial speed will be
acceleration is due to gravity
now we can use this to find the height
so maximum allowed height will be 20.4 m
<span>Two plastic balls suspended by strings are placed close to each other. If they have the same charge then they will repel each other.</span>