Chapter 6, Problem 20A

How much air resistance acts on a falling 100-N box of nails when it reaches terminal velocity?

To determine

The air resistance acting on a falling $100\text{-N}$ box of nails when it reaches terminal velocity.

Answer to Problem 20A

  $100\text{N}$

Explanation of Solution

Introduction:

When an object falls with its terminal velocity, then it means that no net acceleration is acting on it or the object moves with a constant velocity.

Since when the object reaches the terminal velocity, the net acceleration of the object is zero. Hence, for the given box of nails, it can be written as,

  $\begin{array}{c}100-F_{\text{air}}=0\\ F_{\text{air}}=100\text{N}\end{array}$

Where, $F_{\text{air}}=$ air resistance for the given case

Conclusion:

Hence, the air resistance acting on a falling given box of nails, when it reaches terminal velocity, is $100\text{N}$ .