A jet pack is a type of rocket system that can allow a human to "fly" for short
distances. What can you infer about how jet
packs work?
The thrust created by a jet pack must be greater than the
force of gravity acting on the user and the pack.
The user must weigh less than the jet pack to lift off the
ground.
The weight of the fuel in the jet pack must be greater than
the weight of the user in order to achieve liftoff.
The force of gravity on the user must decrease as he is
lifted off the ground.