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2 years ago

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Dane is holding an 8 kilogram box 2 metres above the ground. How much energy is in the box's gravitational potential energy stor

e? Assume Dane is on Earth, where g = 10 N/kg.

1 answer:

9966 [12]2 years ago

4 0

156.8 Joules of energy is in the box's gravitational potential energy store

<u>Explanation</u>:

<em>Given:</em>

Mass of the box Dane is holding = 8 Kilograms

Height at which Dane is holding the box above the ground= 2 metres

<em>To Find:</em>

Gravitational potential energy in the box=?

<em>Solution:</em>

gravitational potential energy is the work done per mass on a object to move that object from one fixed location to to another location against gravity.Its unit is joules or J

Thus Gravitational potential energy is represented as,

$PE_g=mgh$

where

$PE_g$ is the gravitational potential energy

m is the mass

h is the height

g is the gravitational force( 9.8 $m/s^2$ )

Now substituting the given values,

$PE_g=8\times 9.8\times 2$

$PE_g=156.8 Joules$

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For the two expressions mentioned above remember that the variables mean

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Replacing this value we have then

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$\frac{A_1}{A_2} = \sqrt{2} \sqrt{\frac{m_1}{m_1}}$

But the value of the mass was previously given, then

$\frac{A_1}{A_2} = \sqrt{2} \sqrt{\frac{m}{2m}}$

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Two balls with charges +Q and +4Q are separated by 3R. Where should you place another charged ball Q0 on the line between the tw

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yes independent of the sign or valve of Q

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$U1/U2=6$
$U1/U2=6$

From the question we are told that

Question 1

Charge q1 is distance r from a positive point charge Q.

Question 2

Charge q2=q1/3 is distance 2r from Q.

Charge q1 is distance s from the negative plate of a parallel-plate capacitor.

Charge q2=q1/3 is distance 2s from the negative plate.

Generally the equation for the potential energy is mathematically given as

$U=\frac{-k*qQ}{r}$

Therefore

The Equations of U1 and U2 is

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Since

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1 year ago

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Answer:

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If we replace m with the mass rate M we obtain the rate of change in potential energy over time, so the power generated:

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1 year ago

A 26 cm object is 18 cm in front of a plane mirror. A ray of light strikes the object and is reflected off the mirror at a 42-de

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Answer:

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So, since in this case the angle of incidence is 42 degrees, the angle of reflection is also 42 degrees.

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