Chapter 4, Problem 41A

To determine

The net force acting on a ball which is moving at a constant velocity.

Answer to Problem 41A

  $0\text{N}$

Explanation of Solution

Given:

The mass of the ball is $1.0\text{ kg}$ and it is moving at a constant velocity.

Formula used:

The acceleration of an object can be obtained by,

  $a=\frac{\Delta v}{\Delta t}=\frac{v_f-v_i}{t_f-t_i}$

Where, $\Delta v$ is change in velocity in time interval $\Delta t$ .

From Newton’s second law of motion:

  $F_{net}=ma$

Where, a is the acceleration, m is the mass and $F_{net}$ is the net force.

Calculation:

Now, it is given that the ball is moving at a constant velocity, then the acceleration of the ball will be,

  $\begin{array}{c}a=\frac{\Delta v}{\Delta t}\\ =\frac{0}{\Delta t}=0{\text{m/s}}^{\text{2}}\end{array}$

Thereby, the net force acting on the ball will also be zero.

  $\begin{array}{c}{F}_{net}=m\times a\\ =0\text{N}\end{array}$

Conclusion:

Thus, the net force acting on the given ball is 0N.