Chapter 6, Problem 38A

An aircraft gains speed during takeoff due to the constant thrust of its engines. When is the acceleration during takeoff greatest—at the beginning of the run along the runway or just before the aircraft lifts into the air? Think, then explain.

To determine

When is the acceleration during takeoff greatest.

Answer to Problem 38A

At the beginning of the takeoff, the acceleration is greater.

Explanation of Solution

Introduction:

Unbalanced forces that are acting on a body cause the acceleration of the body. For a constant force, acceleration decreases as the mass increases.

Description:

According to Newton’s second law of motion, the force is defined as:

  $F=ma$

In the given situation, the air drag is least during the takeoff of the aircraft. So, it can be concluded that acceleration is greatest at the beginning of the takeoff. At the beginning of the takeoff, the aircraft needs higher speed.

Hence, the acceleration is greatest at the beginning of takeoff.

Conclusion:

At the beginning of the takeoff, the acceleration is greater.