Answer:
The time it can operate between chargins in minutes is
[tex]t=102.8 minutes[/tex]
Explanation:
Given: [tex]m=500kg[/tex], [tex]r=1.0m[/tex], [tex]w=200\pi rad/s[/tex]
a). The rotational kinetic energy
[tex]K_R=\frac{1}{2}*I*w^2[/tex]
[tex]I=\frac{1}{2}*m*r^2[/tex]
[tex]I=\frac{1}{2}*500kg*(1.0m)^2[/tex]
[tex]I=250 kg*m^2[/tex]
[tex]K_R=\frac{1}{2}*250kg*m^2*(200\pi rad/s)^2[/tex]
[tex]K_R=49.348x10^6J[/tex]
b). The power average 0.8kW un range time can be find
[tex]P=\frac{K_R}{t'}[/tex]
Solve to t'
[tex]t=\frac{K_R}{P}[/tex]
[tex]t=\frac{49.348x10^6}{0.8x10^3w}=6168.5s[/tex]
[tex]t=6168.5s\frac{1minute}{60s}=102.8 minutes[/tex]
