What is the gravitational potential energy of a book with a mass of 0.3 kg on a 1.0 high desk?
3.0 J 30J 0.3J
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Answer: The gravitational potential energy of a book with a mass of 0.3 kg on a 1.0 m high desk is 3.0 J (First option)
Solution:
Mass of the book: m=0.3 kg
Height: h=1.0 m
Gravity's acceleration: g=10 m/s^2
Gravitational potential Energy: Ep=?
Ep=m g h
Replacing the given values:
Ep=(0.3 kg) (10 m/s^2) (1.0 m)
Ep = 3 (kg m/s^2) m
Ep = 3 N m
Ep = 3 Joules
Ep = 3 J