average acceleration

Question

Velocity of a particle changes uniformly from 8 m/s east to 4 m/s west in 3 s. Magnitude of average acceleration?

RankGuru · Accepted Answer

1. **Sign Convention**: Let East be the positive direction ($+$ velocity).
2. **Velocity Change**: 
   - Initial velocity $u = +8$ m/s.
   - Final velocity $v = -4$ m/s (West).
3. **Calculate Change ($\Delta v$)**: $\Delta v = v - u = (-4) - (+8) = -12$ m/s.
4. **Acceleration Formula**: $a_{avg} = \frac{\Delta v}{\Delta t} = \frac{-12 \text{ m/s}}{3 \text{ s}} = -4 \text{ m/s}^2$.
5. **Magnitude**: $|a_{avg}| = 4 \text{ m/s}^2$.
6. **Result**: The magnitude of average acceleration is **$4$ m/s²**.

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average acceleration

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