1. a 63.0 - kg sprinter starts a race with an acceleration of 4.20 m/s². what is the net external force on…

1. a 63.0 - kg sprinter starts a race with an acceleration of 4.20 m/s². what is the net external force on him? 2. if the sprinter from the previous problem
Answer
Explanation:
Step1: Identify the formula
We use Newton's second - law $F = ma$, where $F$ is the net force, $m$ is the mass and $a$ is the acceleration.
Step2: Substitute the given values
Given $m = 63.0\ kg$ and $a=4.20\ m/s^{2}$. Substitute into the formula: $F=(63.0\ kg)\times(4.20\ m/s^{2})$.
Step3: Calculate the result
$F = 63.0\times4.20=264.6\ N$. Rounding to three significant digits, $F = 265\ N$.
Answer:
$265\ N$