Chapter 12, Problem 1IP

How much force must be applied by a kicker to give a stationary 2.5-kg ball an acceleration of 40 m/s²? (Answer: 100 N)

Summary Introduction

To determine: The force applied by a kicker on a stationary ball.

Answer to Problem 1IP

The force applied by a kicker on a stationary ball is $100\text{N}$.

Explanation of Solution

Calculation:

Write an expression to find the force.

$F=ma$

Here, m is the mass of the ball, a is the acceleration, and F is the force on ball.

Substitute 2.5 kg for m and $40\text{m}/{\text{s}}^{\text{2}}$ for a to find the force.

$\begin{array}{c}F=\left(2.5\text{kg}\right)\left(40\text{m}/{\text{s}}^{\text{2}}\right)\\ =100\text{kg}\text{m}/{\text{s}}^{\text{2}}\left(\frac{1\text{N}}{\text{kg}\text{m}/{\text{s}}^{\text{2}}}\right)\\ =100\text{N}\end{array}$

Conclusion

Therefore, the force applied by a kicker on a stationary ball is $100\text{N}$.