Physics question: Mass and Velocity and acceleration and distance.?

Question

An object of mass 3kg is thrown upward at a velocity of 8m/s. How high does it go?

Is this a trick question? I can't find a formula that includes mass... so is the given mass irrelevant in this question? Please help. Thanx everyone.

Answer 1

Using conservation of Energy...

1/2 m v² = m g h

we see that mass cancels out (everything falls at the same acceleration, regardless of mass) and we have

h = 1/2 v² / g = 3.3 m

Answer 2

Mass is irrelevant.

vf^2 = vi^2 - 2gh

0 = 8^2 - 2*9.8*h

h = 64/19.6 = 3.27 m

Answer 3

No.  The mass is not a factor for short distances and high density objects (try throwing a 3 kg feather up at 8 m/sec).