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3 years ago

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A student in Denver (altitude = 1 mile = 1609 m above sea level) brings a physics book of mass 1.3 kg to the top of a ten story

building of height 26 m and holds the book over her head 151 cm above the roof. What is the gravitational potential energy Ug of the book?

1 answer:

Nesterboy [21]3 years ago

8 0

Answer:

Explanation:

Potential energy is the energy of a body due to is virtue of rest.

Potential energy is given as mgh

g is a constant and it is 9.81m/s²

And also the mass of the body is given as 1.3kg

Now the height of the body is

He took a book to a storey building of height 26m

He still holds the book 151 cm (1.51m) above the house.

The house is on an altitude of 1609m from the sea level.

Total Ug with out the sea level is

Ug=mgh

Ug=1.3 × 9.81 ×(26+1.51)

Ug=350.84J

Then, the potential energy due to the sea level is given as

Ug=mgh

Where g = 1/6371 m/s²

Therefore

Ug=mgh

Ug=1.3 × 1/6371 ×1609

Ug=0.328J

Total energy = 0.328+350.84

Ug=351.17J

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