v = √(2 E/m)
Since the engine is 25% efficient, the energy available to propel the
car is 48,000 × 0.25 or 12,000 joules. So
v = √(24,000/1,000) = 2√6 = 4.9 meters per second
* * * * * * *
e = (300 - 20)/300 = 14/15 = 0.93 = 93%
The crossover point, t, in hours is found by equating the nuclear power
plant mass and that of the fuel cell with its associated fuel. The
equation is
1000 = 50 + 25 + ½t
t = 1850 hours = 77 days
* * * * * * *