In introductory mechanics, momentum is defined as $p=mv$. What are the SI units of momentum?

• A. $kg\cdot \frac{m}{s}$
• B. $N\cdot m$
• C. $kg\cdot \frac{m}{s^2}$
• D. $kg\cdot \frac{m^2}{s^2}$

Answer: (A)

Verified step by step guidance

1. Recall the definition of momentum in mechanics: \(p = m v\), where \(p\) is momentum, \(m\) is mass, and \(v\) is velocity.
2. Identify the SI unit of mass \(m\), which is the kilogram (kg).
3. Identify the SI unit of velocity \(v\), which is meters per second (m/s).
4. Since momentum is the product of mass and velocity, multiply their units: \(\text{kg} \times \frac{\text{m}}{\text{s}}\).
5. Conclude that the SI unit of momentum is kilogram meter per second, written as \(\text{kg} \cdot \frac{\text{m}}{\text{s}}\).