what minimum speed does a 100g puck need to make it to the top of a 3m long 20degree frictionless ramp?

Answer 1

Enough speed such that the initial kinetic energy (1/2)MV^2, equals the potential energy gain at maximum elevation, M g H.

M cancels out, so you don't need to know the mass. You DO need to calculate H. Use trigonometry.

Answer 2

mgh=1/2mv^2

To find h

sin 20= h/3
Put h and g in above equation and you are happpy :)

Answer 3

This sucked, terrible explanation