- #1

adriannesmith

- 5

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## Homework Statement

Dan is gliding on his skateboard at 3.00m/s . He suddenly jumps backward off the skateboard, kicking the skateboard forward at 6.00m/s (as measured by an observer on the ground). Dan's mass is 40.0kg and the skateboard's mass is 5.00kg . How fast is Dan going as his feet hit the ground?

## Homework Equations

vf-vi=vexplosion*ln(mf/mi)

## The Attempt at a Solution

vi=3 m/s

mi=45 kg

mf of dan=40 kg

I used 6 m/s as vex

when I plugged the above in the equation to find vf I got 2.29 which was marked wrong. Is it wrong to use 6m/s for Vex?