The same type of engine is placed in two different airplanes. The first airplane is twice as heavy as the second airplane. Which statement is correct about the mass of the airplane and its acceleration, assuming a constant net force?(1 point)

Responses

Decreasing the mass of the airplane will result in the airplane accelerating less.
Decreasing the mass of the airplane will result in the airplane accelerating less.

Increasing the acceleration of the airplane causes the engine to provide less force.
Increasing the acceleration of the airplane causes the engine to provide less force.

Decreasing the mass of the airplane will result in the airplane accelerating more.
Decreasing the mass of the airplane will result in the airplane accelerating more.

Increasing the acceleration of the airplane causes the engine to provide more force.

1 answer

To analyze the situation of two airplanes with the same type of engine but different masses, we can apply Newton's second law of motion, which is stated as:

\[ F = ma \]

Where:

  • \( F \) is the net force,
  • \( m \) is the mass,
  • \( a \) is the acceleration.

Given that the first airplane is twice as heavy as the second airplane, we can denote the mass of the second airplane as \( m \) and the mass of the first airplane as \( 2m \).

  1. If the net force applied by the engine is constant for both airplanes:
    • For the second airplane (lighter): \( F = m a_2 \) ⇒ \( a_2 = \frac{F}{m} \)
    • For the first airplane (heavier): \( F = 2m a_1 \) ⇒ \( a_1 = \frac{F}{2m} \)

According to these equations:

  • The lighter airplane (mass \( m \)) will have greater acceleration (\( a_2 \)) than the heavier airplane (mass \( 2m \)), which will have lower acceleration (\( a_1 \)) because the force is the same, but the mass is different.

Now, looking at the provided statements:

  1. Decreasing the mass of the airplane will result in the airplane accelerating less. - Incorrect. Decreasing mass would increase acceleration.

  2. Increasing the acceleration of the airplane causes the engine to provide less force. - Incorrect. Increasing acceleration requires more force if mass remains constant.

  3. Decreasing the mass of the airplane will result in the airplane accelerating more. - Correct! Less mass with the same force yields greater acceleration.

  4. Increasing the acceleration of the airplane causes the engine to provide more force. - Correct in a general sense, but the statement is about a direct relation of acceleration to the force provided by the engine which can be misinterpreted.

The correct answer is: Decreasing the mass of the airplane will result in the airplane accelerating more.