英文關鍵字
bouncing
colliding
collision
elastically
energy
equation
force
gravitation
gravity
inelastically
intact
intrinsic
kinetic
objects
physics
potential
property
relative
speed
two
velocity
英文關鍵字
bouncing
colliding
collision
elastically
energy
equation
force
gravitation
gravity
inelastically
intact
intrinsic
kinetic
objects
physics
potential
property
relative
speed
two
velocity