Which has more momentum, a heavy truck moving at 30 km/h or a light truck moving at 30 km/h?

1. Break Down the Problem

To determine which truck has more momentum, we need to analyze the concept of momentum. Momentum is defined as the product of mass and velocity.

2. Relevant Concepts

The formula for momentum ($p$) is: $p = m \cdot v$ where:

• $p$ is momentum,
• $m$ is mass (in kilograms),
• $v$ is velocity (in meters per second).

3. Analysis and Detail

• Both trucks are moving at the same speed, which is 30 km/h. We first need to convert this speed into meters per second for consistency with SI units: $30 \, \text{km/h} = \frac{30 \times 1000 \, \text{m}}{3600 \, \text{s}} = 8.33 \, \text{m/s}$

• Let $m_1$ be the mass of the heavy truck and $m_2$ be the mass of the light truck. We assume $m_1 > m_2$.

• The momentum of the heavy truck is: $p_1 = m_1 \cdot 8.33 \, \text{m/s}$

• The momentum of the light truck is: $p_2 = m_2 \cdot 8.33 \, \text{m/s}$

4. Verify and Summarize

Since $m_1 > m_2$, it follows that $p_1 > p_2$. Therefore, the heavy truck will have a greater momentum than the light truck when both are moving at the same speed of 30 km/h.

Final Answer

The heavy truck moving at 30 km/h has more momentum than the light truck moving at the same speed.