- The correct response is: The truck has more kinetic energy because it has a greater mass.
Kinetic energy is calculated using the formula \( KE = \frac{1}{2} mv^2 \), where \( m \) is mass and \( v \) is velocity. Assuming the truck and car are moving at the same speed, the truck, having greater mass, will have more kinetic energy.
- To determine which object has the greatest kinetic energy, we can use the kinetic energy formula \( KE = \frac{1}{2} mv^2 \).
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For the red car: \[ KE = \frac{1}{2} \times 500 \text{ kg} \times (3 \text{ m/s})^2 = \frac{1}{2} \times 500 \times 9 = 2250 \text{ J} \]
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For the blue car: \[ KE = \frac{1}{2} \times 500 \text{ kg} \times (30 \text{ m/s})^2 = \frac{1}{2} \times 500 \times 900 = 225000 \text{ J} \]
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For the yellow car: \[ KE = \frac{1}{2} \times 500 \text{ kg} \times (12 \text{ m/s})^2 = \frac{1}{2} \times 500 \times 144 = 36000 \text{ J} \]
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For the green car: \[ KE = \frac{1}{2} \times 500 \text{ kg} \times (21 \text{ m/s})^2 = \frac{1}{2} \times 500 \times 441 = 110250 \text{ J} \]
Based on these calculations, the object with the greatest kinetic energy is: a blue car with a mass of 500 kg moving at 30 m/s (225000 J).
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