To determine which situation has the greatest momentum, we must calculate the momentum for each scenario. Recall the formula for momentum, $p = mv$, where $p$ is momentum, $m$ is mass, and $v$ is velocity. Additionally, the impulse-momentum theorem relates force, time, and momentum, such that:

$p = F \cdot t$

Let's analyze each option:

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Option A: A car accelerates from rest to 3.0 m/s

• No mass is given, so momentum can't be calculated directly.
• However, assuming a constant mass $m$, the final momentum is proportional to $m \cdot 3.0 \, \text{m/s}$.

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Option B: A baseball hit with a net force of 10.0 N for 3.0 s

Using impulse: $p = F \cdot t = 10.0 \, \text{N} \cdot 3.0 \, \text{s} = 30.0 \, \text{kg} \cdot \text{m/s}$

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Option C: A rocket crashes back to Earth with a force of 50.0 N for 0.3 s

Using impulse: $p = F \cdot t = 50.0 \, \text{N} \cdot 0.3 \, \text{s} = 15.0 \, \text{kg} \cdot \text{m/s}$

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Option D: A boxer hits a punching bag with a net force of 30.0 N for 0.5 s

Using impulse: $p = F \cdot t = 30.0 \, \text{N} \cdot 0.5 \, \text{s} = 15.0 \, \text{kg} \cdot \text{m/s}$

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Comparison of Momentum:

• Option A: Cannot be directly compared without mass.
• Option B: $30.0 \, \text{kg} \cdot \text{m/s}$
• Option C: $15.0 \, \text{kg} \cdot \text{m/s}$
• Option D: $15.0 \, \text{kg} \cdot \text{m/s}$

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Conclusion:

The greatest momentum is in Option B: A baseball hit with a net force of 10.0 N for 3.0 s.

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Would you like more clarification on the calculation process? Here are five follow-up questions to deepen your understanding:

1. What is the relationship between force, time, and momentum?
2. How is the impulse-momentum theorem used in physics?
3. How would the car's momentum in Option A compare if its mass was given?
4. Why does the rocket in Option C have a lower momentum despite a higher force?
5. Can impulse be negative, and what does that mean physically?

Tip: Always check for proportional relationships (like $p = mv$ or $p = F \cdot t$) when comparing scenarios without complete information!