Exam-style question
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A ball is dropped from a height of 20 meters. Calculate the gravitational potential energy (GPE) of the ball just before it is dropped. Use g = 9.81 N/kg.
Model answer
What a good answer should say
- The gravitational potential energy (GPE) of the ball is 196.2 J.
Explanation
Why this works
The calculation uses the formula for gravitational potential energy, GPE = mgh. Substituting the mass (m) as 2 kg (assuming a mass for calculation), height (h) as 20 m, and gravitational field strength (g) as 9.81 N/kg gives GPE = 2 kg * 9.81 N/kg * 20 m = 392.4 J.
This question tests the student's ability to apply the conservation of energy principle in a practical scenario.
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