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3 years ago

If the heat of fusion is 32.2 kj/mol, the amount of heat energy required to melt 5.67 grams of feo is

1 answer:

3 0

The heat of fusion is the amount of energy required to change the state of one mole of substance from solid to liquid at constant temperature. Therefore, in order to determine the energy needed by a given mass of substance, we must first convert the mass into moles by using:
Moles = mass / Mr
Moles = 5.67 / 71.84
Moles = 0.079 mol

Energy = latent heat of fusion * moles
Energy = 32.2 * 0.079
Energy = 2.544 kJ = 2,544 J

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An apple weighs 1.00 N. When you hang it from the end of a long spring of force constant 1.50 N/m and negligible mass, it bounce

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Answer:

2.67 m

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$f_s=\dfrac{1}{2\pi}\sqrt{\dfrac{k}{m}}$

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Given in the question

$f_p=\dfrac{1}{2}f_s$

$\dfrac{1}{2\pi}\sqrt{\dfrac{g}{l}}=\dfrac{1}{2}\dfrac{1}{2\pi}\sqrt{\dfrac{k}{m}}\\\Rightarrow \sqrt{\dfrac{g}{l}}=\dfrac{1}{2}\sqrt{\dfrac{k}{m}}\\\Rightarrow \dfrac{g}{l}=\dfrac{1}{4}\dfrac{k}{m}\\\Rightarrow l=\dfrac{4gm}{k}\\\Rightarrow l=\dfrac{4\times 9.81\times \dfrac{1}{9.81}}{1.5}\\\Rightarrow l=2.67\ m$

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2 years ago

A 60-kg rollerblader rolls 10 m down a 30? incline. When she reaches the level floor at the bottom, she applies the brakes. The

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Answer:

s = 20 m

Explanation:

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u = 9.89 m/s

Using second law of motion

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a = μ g

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Using third equation of motion ,

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3 years ago

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Answer:

4 seconds

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2 years ago