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guajiro [1.7K]
3 years ago
8

What is the potential energy of a 3 kg rock sitting at the top of a 21 meter high cliff?

Physics
1 answer:
Svetradugi [14.3K]3 years ago
3 0

Answer:

618.03 J

Explanation:

Potential energy can be calculate using the following formula.

PE=m*g*h

where m is the mass, g is the acceleration due to gravity and h is the height.

In this situation, we have a 3 kilogram rock on a 21 meter high cliff. Therefore, the mass is 3 kg and the height is 21 m.

On Earth, the acceleration due to gravity is 9.81 m/s^2.

m=3 kg

h=21 m

g=9.81 m/s^2

Substitute these values into the formula.

PE=3*9.81*21

Multiply all the numbers together

PE=63*9.81

PE=618.03

The potential energy is 618.03 kg m^2/s^2, or 618.03 Joules

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<h2>Answer:</h2>

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<h2>Explanation:</h2>

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y = (m₁y₁ + m₂y₂ + m₃y₃) / M       ----------------(ii)

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m₃ and x₃ = mass and position of third mass in the x direction.

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From the question;

m₁ = 6kg

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