求解壹道物理動量題
設t時刻,飛船質量m,則動量守恒,
mv=m0v0
m=m0v0/v
dm=-m0v0dv/v?=ρSvdt
-m0v0dv/v?=ρSdt
(m0v0/2)/v?=ρSt十C
v?=m0v0/2(ρSt十C)
v=√[m0v0/2(ρSt十C)]
t=0,v=v0
v0=m0/2C
C=m0/2v0
v=√[m0v0/2(ρSt十m0/2v0)]
=v0√[m0/(2ρStv0十m0)]
mv=m0v0
m=m0v0/v
dm=-m0v0dv/v?=ρSvdt
-m0v0dv/v?=ρSdt
(m0v0/2)/v?=ρSt十C
v?=m0v0/2(ρSt十C)
v=√[m0v0/2(ρSt十C)]
t=0,v=v0
v0=m0/2C
C=m0/2v0
v=√[m0v0/2(ρSt十m0/2v0)]
=v0√[m0/(2ρStv0十m0)]