Step-by-step explanation for a 13-year-old on calculating the magnitude of acceleration of an object with a mass of 0.5 kg when three forces act on it in different directions.
Let's break down the problem step by step.
We have two forces pulling (or pushing) to the right and one force pushing to the left. Since forces have directions, we can consider right as positive (+) and left as negative (−).
Add the forces, keeping track of the direction:
Net force, F_net = 7 N + (-9 N) = -2 N
The negative sign means the net force is to the left.
Newton's Second Law states:
F_net = m × a
If we want to find acceleration, rearrange the formula:
a = F_net / m
Substitute values:
a = (-2 N) / 0.5 kg = -4 m/s²
Magnitude is always positive, so:
|a| = 4 m/s²
The net force points to the left with 2 N, and the object accelerates to the left with an acceleration magnitude of 4 meters per second squared.