Posted by Tracey on Saturday, November 27, 2010 at 8:33pm.
Two spheres A and B, where A has twice the mass of B, are projected at the same horizontal velocity off the edge of two different height shelves. Sphere A leaves from a height of 2.0 m. Sphere B leaves a shelf 1.0 m off the floor. If both spheres leave the edge of the table at the same instant, where will sphere A land?

Physics  Damon, Saturday, November 27, 2010 at 8:49pm
The mass has nothing to do with this.
h = .5 g t^2
2 hb = ha
ha = .5 g ta^2
hb = .5 g tb^2
so
ta/tb = sqrt (ha/hb) = sqrt 2
the horizontal speeds are the same so distance proportional to time in air
ta u = tb u sqrt 2
so
da = sqrt 2 * db