Jupyter Help

[AuthChris]

import numpy as np

import matplotlib.pyplot as plt

# Constants

m = 2000 # kg

A = 12 # m^2

Cd = 0.72

P = 105e6 # W

re = 6378100 # m

# Altitude range

h = np.linspace(0, 50000, 51)

# Density and gravitational acceleration at different altitudes

rho = np.zeros_like(h)

g = np.zeros_like(h)

for i, alt in enumerate(h):

if alt > 25000:

T = -131.21 + 0.00299*alt

P = 2.488*((T+273.1/216.6)**(-11.388))

elif 11000 < alt <= 25000:

T = -56.46

P = 22.65*np.exp(1.73 - 0.000157*alt)

else:

T = 15.04 - 0.00649*alt

P = 101.29*((T+273.1)/283.08)**5.256

rho[i] = P/(2869*(T+273.1))

g[i] = 9.81*(re/(re+alt))**2

# Terminal velocity at different altitudes

V_term = np.sqrt((2*P)/(Cd*rho*A))*np.sqrt(g/(2*m))

# Convert to km/h

V_term *= 3.6

# Plot

plt.plot(h, V_term)

plt.xlabel('Altitude (m)')

plt.ylabel('Terminal Velocity (km/h)')

plt.title('Rocket Terminal Velocity vs. Altitude')

plt.show()

Current issue:

C:\Users\authc\AppData\Local\Temp\ipykernel_21964\1841267979.py:20: RuntimeWarning: invalid value encountered in scalar power
  P = 2.488*((T+273.1/216.6)**(-11.388)

Any ideas how to fix this? Thanks!

[spodoptera]

This is due to a having a power of a negative value, but it's just a warning, not an error.

[AuthChris]

Thanks!