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2 years ago

A cinder block is sitting on a platform 20m high. It weighs 7.9kg. The block has potential energy. calculate it

2 answers:

8 0

By definition, the potential energy is
U = m * g * h
Where
m = mass
g = accelecarion of gravity
h = height
Substituting
U = (7.9) * (9.8) * (20) = 1548.4J
The block has a potential energy of 1548.4J
Note: assuming reference level on the ground

Goshia [24]2 years ago

7 0

<span>The formula for potential energy is mass * gravity * height. With height given as 20m and weight given as 7.9kg, we can fill in 7.9 * gravity * 20. Gravity is 9.8m/s constant so 7.9 * 9.8 * 20 = potential energy. The result is 1549.45, with the unit of energy being joules. Final answer 1549.45 J</span>

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The mass of the crate is 5kg.

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Okay, haven't done physics in years, let's see if I remember this.

So Coulomb's Law states that $F = k \frac{Q_1Q_2}{d^2}$ so if we double the charge on $Q_1$ and double the distance to $(2d)$ we plug these into the equation to find

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2 years ago

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