An airplane carries 320 passengers from Phoenix to Los Angeles flying at an average speed of 490 miles per hour. On the return flight, the plane carries 164 passengers and travels at the same average speed. What happens to the plane's kinetic energy?(1 point)

Question

Responses

The plane's kinetic energy is the same on both flights.
The plane's kinetic energy is the same on both flights.

On the return flight, the plane has less kinetic energy.
On the return flight, the plane has less kinetic energy.

The plane's kinetic energy is changed to potential energy when it lands.
The plane's kinetic energy is changed to potential energy when it lands.

On the return flight, the plane has more kinetic energy.

Answer 1

The plane's kinetic energy depends on its mass and its velocity, and it can be expressed using the formula:

\[ KE = \frac{1}{2} mv^2 \]

where \( KE \) is kinetic energy, \( m \) is the mass of the airplane (including passengers), and \( v \) is the velocity.

In this scenario, although the speed of the airplane remains the same at 490 miles per hour on both flights, the mass of the airplane changes because it carries different numbers of passengers.

1. First Flight (Phoenix to Los Angeles):

   • Passengers: 320.
   • Mass of the airplane is greater due to more passengers.

2. Return Flight (Los Angeles to Phoenix):

   • Passengers: 164.
   • Mass of the airplane is less due to fewer passengers.

Given that kinetic energy is directly proportional to mass (as long as speed remains constant), the return flight (with 164 passengers) results in less kinetic energy compared to the outward flight (with 320 passengers).

Therefore, the correct response is:

On the return flight, the plane has less kinetic energy.