To compare the kinetic and potential energies of the two watermelons, we can use the formulas for kinetic energy (KE) and potential energy (PE):
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Kinetic Energy (KE) is calculated using the formula: \[ KE = \frac{1}{2} mv^2 \] where \( m \) is the mass and \( v \) is the speed of the object.
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Potential Energy (PE) depends on height, but since the height is not given, we can't directly compare potential energies without it. However, we can assume that both fruits are at the same height when they fall, so any potential energy at that height will be the same for both.
Now let's calculate the kinetic energies for both watermelons:
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Watermelon A:
- Mass (m) = 4 kg
- Speed (v) = 2 m/s \[ KE_A = \frac{1}{2} \times 4 \times (2)^2 = \frac{1}{2} \times 4 \times 4 = 8 , \text{J} \]
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Watermelon B:
- Mass (m) = 4 kg
- Speed (v) = 4 m/s \[ KE_B = \frac{1}{2} \times 4 \times (4)^2 = \frac{1}{2} \times 4 \times 16 = 32 , \text{J} \]
Comparison:
- Watermelon A has a kinetic energy of 8 J.
- Watermelon B has a kinetic energy of 32 J.
Since Watermelon A has a lower speed, it also has lower kinetic energy. However, both watermelons would have the same potential energy if they are at the same height.
Conclusion: The correct answer is: The watermelon B has more kinetic energy.
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