Final answer:
Using the given values for gasoline's energy content and the transfer rate, the energy transfer rate during the refueling of a car is approximately 13.03 MW, confirming the claim that it's close to 15 MW.
Step-by-step explanation:
To verify the claim on page 292 regarding fuel transfer using boost pumps, we will calculate the energy transfer rate when a car is refueled at a gasoline station. The claim suggests that transferring approximately 6 gallons (23 liters) per minute of gasoline, which contains about 34 MJ per liter, results in an energy transfer rate in the neighborhood of 15 MW.
First, we need to establish the energy content per minute:
- Energy per liter = 34 MJ
- Liters per minute = 23
- Total energy per minute = Energy per liter × Liters per minute = 34 MJ/liter × 23 liters/minute = 782 MJ/minute
To convert megajoules per minute to megawatts, we take into account that 1 watt = 1 joule/second, and there are 60 seconds in a minute, hence:
- 1 MJ = 106 J
- 1 MW = 106 W
- Energy transfer rate (in MW) = Total energy per minute / 60
- Energy transfer rate (in MW) = 782 MJ/minute ÷ 60 = 13.03 MW
This calculation demonstrates that the energy transfer rate when refueling is approximately 13.03 MW, which is in accord with the neighborhood of 15 MW as claimed. Thus, it is clear that the boost pumps used to refuel vehicles at a gasoline station are capable of transferring energy at a very high rate.