Дано:
R = 0,5 км = 500 м;
![\frac{P_{max}}{P_{min}}](https://tex.z-dn.net/?f=+%5Cfrac%7BP_%7Bmax%7D%7D%7BP_%7Bmin%7D%7D+)
= 4.
V - ?
Решение:
![P_{max}](https://tex.z-dn.net/?f=+P_%7Bmax%7D+)
= m (g + a) = m (g +
![\frac{V^{2}}{R}](https://tex.z-dn.net/?f=+%5Cfrac%7BV%5E%7B2%7D%7D%7BR%7D+)
);
![P_{min}](https://tex.z-dn.net/?f=+P_%7Bmin%7D+)
= m (g - a) = m (g -
![\frac{V^{2}}{R}](https://tex.z-dn.net/?f=+%5Cfrac%7BV%5E%7B2%7D%7D%7BR%7D+)
).
![\frac{P_{max}}{P_{min}}](https://tex.z-dn.net/?f=+%5Cfrac%7BP_%7Bmax%7D%7D%7BP_%7Bmin%7D%7D+)
=
![\frac{m (g + \frac{V^{2}}{R})}{m (g - \frac{V^{2}}{R})}](https://tex.z-dn.net/?f=+%5Cfrac%7Bm+%28g+%2B+%5Cfrac%7BV%5E%7B2%7D%7D%7BR%7D%29%7D%7Bm+%28g+-+%5Cfrac%7BV%5E%7B2%7D%7D%7BR%7D%29%7D+)
= 4;
![{m (g + \frac{V^{2}}{R})} = 4*{m (g - \frac{V^{2}}{R})}](https://tex.z-dn.net/?f=%7Bm+%28g+%2B+%5Cfrac%7BV%5E%7B2%7D%7D%7BR%7D%29%7D+%3D+4%2A%7Bm+%28g+-+%5Cfrac%7BV%5E%7B2%7D%7D%7BR%7D%29%7D+)
;
![{g + \frac{V^{2}}{R}} = {4g - 4\frac{V^{2}}{R}}](https://tex.z-dn.net/?f=%7Bg+%2B+%5Cfrac%7BV%5E%7B2%7D%7D%7BR%7D%7D+%3D+%7B4g+-+4%5Cfrac%7BV%5E%7B2%7D%7D%7BR%7D%7D+)
;
![{5\frac{V^{2}}{R}} = {3g}](https://tex.z-dn.net/?f=%7B5%5Cfrac%7BV%5E%7B2%7D%7D%7BR%7D%7D+%3D+%7B3g%7D+)
;
5V² = 3gR;
V =
![\sqrt{ \frac{3}{5}gR}](https://tex.z-dn.net/?f=+%5Csqrt%7B+%5Cfrac%7B3%7D%7B5%7DgR%7D)
.
Вычисления:
V =
![\sqrt{ \frac{3}{5}*10*500}](https://tex.z-dn.net/?f=+%5Csqrt%7B+%5Cfrac%7B3%7D%7B5%7D%2A10%2A500%7D)
=
![\sqrt{3000}](https://tex.z-dn.net/?f=+%5Csqrt%7B3000%7D)
≈ 54,8 (м/с).
V = 54,8 м/с = 197,3 км/ч.
Ответ: 54,8 м/с или 197,3 км/ч.
Q=c*m*дельтаt=4,2*0,25*5=5,25кДж(так как теплоёмкость воды:4,2 кДж/кг*град.250 г= 0,25кг)
Ответ:5,25кДж
Р=м*vР=100*3=300кг/м/c.Р штрих=м*v штрих=100*2=200кг/м/c.дельта Р - изменение Р<span>дельта Р=Р штрих-Р=200-300=-100кг/м/c.</span>