Question

how do i find the mass of an object with 3m/s

Answer 1

Only velocity is given??

Answer 2

yes

Answer 3

this is the question "A children's roller coaster is released from the top of a track, if its maximum speed at ground level is 3 m/s. find the height that its released from.

Answer 4

kinetic energy

Answer 5

you do not need the mass

At the 'ground level' it has a speed of 3 m/s which gives it a KE of 0.5 mv^2

At the top of the track it has a PE of mgh

The PE is converted to PE when it rolls down so:

mgh = 0.5mv^2 and you can see that the mass cancels out

h=0.5v^2/g

Answer 6

@jose8787

u=0 m/s
v=3 m/s
a=g=9.81 m/s^2
\[v ^{2}=u ^{2}+2as \]
\[s=v ^{2}/2g\]
s=h= 9/s*9.81
s=.45 m