Mv+mV = 0 (в векторном виде) =>
Mv=mV (уже не в векторном) => M= mV/v = 40*4/0.5 = 40*8=320 кг.
A =
![\frac{V2 - V1}{t}](https://tex.z-dn.net/?f=%20%5Cfrac%7BV2%20-%20V1%7D%7Bt%7D%20)
=
![\frac{28 - 40}{60}](https://tex.z-dn.net/?f=%20%5Cfrac%7B28%20-%2040%7D%7B60%7D%20)
= -12/60 = -0.2
F = ma = - 500000 * 0.2 = - 100000 H
P₁ = 2*10⁵ Па
T = 273+127 = 400 К
![m_{2} = \frac{ m_{1} }{2}](https://tex.z-dn.net/?f=+m_%7B2%7D+%3D++%5Cfrac%7B+m_%7B1%7D+%7D%7B2%7D+)
T₂ = 350 К
p₂ - ?
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Т.к. газ находится в одном и том же сосуде, V₁=V₂.
![pV = \frac{m}{M} RT =\ \textgreater \ V = \frac{mRT}{Mp} ](https://tex.z-dn.net/?f=pV+%3D++%5Cfrac%7Bm%7D%7BM%7D+RT+++%3D%5C+%5Ctextgreater+%5C+++V+%3D++%5Cfrac%7BmRT%7D%7BMp%7D++%0A)
![\frac{ m_{1}R T_{1} }{M p_{1} } = \frac{ m_{2}R T_{2} }{M p_{2} }](https://tex.z-dn.net/?f=+%5Cfrac%7B+m_%7B1%7DR+T_%7B1%7D++%7D%7BM+p_%7B1%7D+%7D++%3D++%5Cfrac%7B+m_%7B2%7DR+T_%7B2%7D++%7D%7BM+p_%7B2%7D+%7D+)
![\frac{ m_{1}R T_{1} }{M p_{1} } = \frac{ m_{1}R T_{2} }{2M p_{2} }](https://tex.z-dn.net/?f=+%5Cfrac%7B+m_%7B1%7DR+T_%7B1%7D++%7D%7BM+p_%7B1%7D+%7D++%3D++%5Cfrac%7B+m_%7B1%7DR+T_%7B2%7D++%7D%7B2M+p_%7B2%7D+%7D+)
![p_{2} = \frac{ Mp_{1}* m_{1}R T_{2} }{ m_{1}R T_{1} *2M } = \frac{ p_{1} T_{2} }{2 T_{1} } = \frac{ 2*10^{5}*350 }{2*400} = 0,875*10^{5} = 87,5*10^{3}](https://tex.z-dn.net/?f=+p_%7B2%7D+%3D++%5Cfrac%7B+Mp_%7B1%7D%2A+m_%7B1%7DR+T_%7B2%7D+++%7D%7B+m_%7B1%7DR+T_%7B1%7D+%2A2M+%7D+%3D++%5Cfrac%7B+p_%7B1%7D+T_%7B2%7D++%7D%7B2+T_%7B1%7D+%7D++%3D++%5Cfrac%7B+2%2A10%5E%7B5%7D%2A350+%7D%7B2%2A400%7D+%3D++0%2C875%2A10%5E%7B5%7D+%3D++87%2C5%2A10%5E%7B3%7D++)
Па = 87,5 кПа.
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p₂ = 87,5 кПа.
Пары ртути - опасны для человека.
Значит в газообразном , или при большой температуре.