[问答题]
Can the diver of Figp j/0v1dhl;-7uut k kfb9 ax (j .r;(ztl8t9fuzdann). 8–29 do a somersault without having any initial rotation when she leaveu(n;xr9anl (t f9d8 t.zb)zjas the board?
参考答案:
In order to do a somersault, the
diver needs some initial angular momentum when she leaves the diving board,
because angular momentum will be conserved during the free-fall motion of the
dive.She cannot exert a torque on
herself in isolation, and so if there is no angular momentum initially, there
will be no rotation during the rest of the dive.