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3 years ago

9

Melissa uses bags of mulch that weigh 40 pounds each. She needs to carry 10 bags to her truck. She usually carries one bag at a

time. Would she do less work if she carried two bags at a time?
No; she would have to use half the force over twice the distance.

Yes; she makes fewer trips, decreasing the distance.

No; she would have to use twice the force over half the distance.

Yes; she decreases both force and distance.

2 answers:

KatRina [158]3 years ago

7 0

Answer: Option (a) is the correct answer.

Explanation:

Work done is related to force as force times displacement.

Mathematically, W = F × d

where W = work

F = force

d = displacement

Therefore, when Melissa carried two bags at a time then she is applying twice the force she was applying earlier. Hence, she have to apply half the force twice the distance.

Thus, we can conclude that no; she would have to use half the force over twice the distance.

umka21 [38]3 years ago

6 0

NO:she would have to use twice the force over half the distance

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$n_{n}$ : is the number of navy beans = 100

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$\%_{b} = \frac{173}{300} \times 100 = 57.7 \%$

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Explanation:

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We need to calculate the change of Gibbs free energy of diamond

Using formula of gibbs free energy

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Using formula of Gibbs free energy

$\beta= \Delta G_{g}+\Delta G+\Delta G_{d}$

$\beta=V(-\Delta P_{g})+\Delta G+V\Delta P_{d}$

$\beta=\Delta P(V_{d}-V_{g})+\Delta G$

Put the value into the formula

$0=\Delta P(\dfrac{12\times10^{-6}}{3.51}-\dfrac{12\times10^{-6}}{2.25})\times10130+2895.3$

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Using formula of Gibbs free energy

$\Delta G=\Delta H-T\Delta S$

Put the value into the formula

$\Delta G=(1897-0)-900\times(2.38-5.73)$

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Hence, (a). The Gibbs free energy change is 2.895 kJ and its positive.

(b). The Gibbs free energy change is 34.59 J/mole

(c). The pressure is 14924 atm.

(d). The Gibbs free energy of diamond relative to graphite is 4912 J.

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