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3 years ago

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A person travels by car from Tucson to Phoenix at a constant speed of 75 km/hr. They then return from Phoenix to Tucson at a con

stant speed of 65 km/hr. What was their average velocity?

1 answer:

kompoz [17]3 years ago

7 0

Answer:

$v=0$

Explanation:

Knowing that the formula for average velocity is:

$v=\frac{x_{2}-x_{1}}{t_{2}-t_{1}}$

Being said that, we know that the person's displacement is zero because it returns to its starting point

$x_{2}=x_{1}$

That means $x_{2}-x_{1}=0$

$v=\frac{0}{t_{2}-t_{1}}=0$

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Answer:

e. 1.2 x 10²³

Explanation:

According to the problem, The current equation is given by:

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The relation between current and number of charge carriers is:

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Here the limits of integration is from 0 to infinite. So,

$q=\int\limits {0.88e^{-t/6\times3600s}}\, dt$

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2 years ago

True [87]

Answer:

$\Delta T=3.615^{\circ}C$ is the drop in the water temperature.

Explanation:

Given:

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<u>Apply the conservation of energy:</u>

Heat absorbed by the ice for melting is equal to the heat lost from water to melt ice.

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stiks02 [169]

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Explanation:

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