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2 years ago

A crane lifts an l-bean to a height of 30 meters giving it a potential energy of 108,486). What is the mass of the I-beam?

Physics

1 answer:

andrew-mc [135]2 years ago

5 0

369 kg

Explanation:

Step 1:

We know that the expression for potential energy is

PE = mgh

where, m =Mass

g = Acceleration due to gravity

h Height

Step 2:

Here m = ?

PE = 108486

h = 30 m

g = 9.8 ms⁻²

108486 = $30 * 9.86 * m$

$m= 108486 / (9.8*30) = 369 kg$

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2 years ago

Biologists use optical tweezers to manipulate micron-sized objects using a beam of light. In this technique, a laser beam is foc

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Explanation:

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2 years ago

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Answer:

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The equation for change of voltage between two points separated a distance d inside parallel conducting plates (<em>which have between them constant electric field</em>) is:

$\Delta V=Ed$

So to calculate our electric field strength we use the fact that the potential 8.8 cm from the zero volt plate is 475 V:

$E=\frac{\Delta V}{d}=\frac{475 V}{8.8cm}=54V/cm$

And we use the fact that the plates are 9.2cm apart to calculate the voltage between them:

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2 years ago

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2 years ago

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Explanation:

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2 years ago