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3 years ago

6

Kyra and Pari are timing how long it takes for 1 g of sugar to dissolve in hot water. Kyra records a time of 24.3 seconds. Pari

records a time of 24 seconds. Whose reading is more precise? Why?

1 answer:

Hoochie [10]3 years ago

7 0

<h3>Answer:</h3><h3>we can say that:-</h3>

A reading with more no of significant figures is considered to be more precise.
Kyra recorded a reading of 24.3 sec. Since all non 0 digits are considered to be significant this reading has 3 significant figures.
Pari recorded a reading of 24 sec. Since all non 0 digits are considered to be significant this reading has 3 significant figures.

<h3>hence we can say that kyra's reading has more significant figures nd so it is more precise.</h3>

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Answer:

x = -1.20 m

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Explanation:

as we know that four masses and their position is given as

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As we know that the formula of center of gravity is given as

$x_{cm} = \frac{m_1 x_1 + m_2x_2 + m_3x_3 + m_4x_4}{m_1 + m_2 + m_3 + m_4}$

$0 = \frac{5(0) + 2.9(0) + 4(2.5) + 8.3 x}{5 + 2.9 + 4 + 8.3}$

$10 + 8.3 x = 0$

$x = -1.20 m$

Similarly for y direction we have

$y_{cm} = \frac{m_1 y_1 + m_2y_2 + m_3y_3 + m_4y_4}{m_1 + m_2 + m_3 + m_4}$

$0 = \frac{5(0) + 2.9(3.2) + 4(0) + 8.3 y}{5 + 2.9 + 4 + 8.3}$

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3 years ago

You may have noticed runaway truck lanes while driving in the mountains. These gravel-filled lanes are designed to stop trucks t

kati45 [8]

Answer:

The coefficient of kinetic friction $\mu_k = 0.724$

Explanation:

From the question we are told that

The length of the lane is $l = 36.0 \ m$

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Generally from the work-energy theorem we have that

$\Delta KE = N * \mu_k * l$

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$\Delta KE = \frac{1}{2} * m * v^2$

=> $\Delta KE = 0.5 * m * 22.6^2$

=> $\Delta KE = 255.38m$

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=> $255.38 = 352.8 * \mu_k$

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3 years ago

Air at 400 kPa, 980 K enters a turbine operating at steady state and exits at 100 kPa, 670 K. Heat transfer from the turbine occ

Angelina_Jolie [31]

Answer:

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tankabanditka [31]

Answer: 148348.6239 kg•m/s

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Like this:

P = 1498.470948 x 99

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I believe that is your answer, hope that helps you even a bit out.

Thanks.

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