Question

a. force needed to accelerate a baseball 7 m/s²: b. force needed to accelerate a baseball object 19 m/s²: c. acceleration of a baseball with a force of 0.75 n:

Explanation:

The mass of a standard baseball is approximately $m = 0.145\ kg$. We will use Newton's second - law of motion, which is given by the formula $F=ma$, where $F$ is the force, $m$ is the mass, and $a$ is the acceleration.

Step1: Recall Newton's second - law formula

$F = ma$

Step2: Solve part a

Given $a = 7\ m/s^{2}$ and $m=0.145\ kg$. Substitute the values into the formula:
$F=0.145\times7$
$F = 1.015\ N$

Step3: Solve part b

Given $a = 19\ m/s^{2}$ and $m = 0.145\ kg$. Substitute the values into the formula:
$F=0.145\times19$
$F=2.755\ N$

Step4: Solve part c

Given $F = 0.75\ N$ and $m = 0.145\ kg$. Rearrange the formula $F = ma$ to solve for $a$, so $a=\frac{F}{m}$.
$a=\frac{0.75}{0.145}$
$a\approx5.17\ m/s^{2}$

Answer:

a. $1.015\ N$
b. $2.755\ N$
c. $5.17\ m/s^{2}$