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2 years ago

12

"On a good day, it takes Mr. Hess 23 minutes (1380 seconds) to drive the 12 miles (19,300 meters). What is his average velocity

on the way to school?"
I uh, don't understand this at all. If someone could help me solve this, I'd greatly appreciate it!

1 answer:

il63 [147K]2 years ago

5 0

Answer:

his average velocity is

$v = \frac{19300}{1380} = 13.9855(m \div s)$

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3 years ago

The strength of the electric field at a certain distance from a point charge is represented by E. What is the strength of the el

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Answer:

E

Explanation:

Using Coulomb's law equation

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3 years ago

The formation of condensation on a glass of ice water causes the ice to melt faster than it would otherwise. If 8.55 g of conden

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Answer:

m = 62.14 g

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3 years ago

A pizza delivery driver must make three stops on her route. She will first leave the restaurant and travel 4 km due north to the

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<h2>5.3 km</h2>

Explanation:

This question involves continuous displacement in various directions. When it becomes difficult to imagine, vector analysis becomes handy.

Let us denote each of the individual displacements by a vector. Consider the unit vectors $\vec{i}\textrm{ and }\vec{j}$ as the unit vectors in the direction of East and North respectively.

By simple calculations, we can derive the unit vectors $\vec{j},\frac{-\vec{i}-\vec{j}}{2}\textrm{ and }\frac{-\frac{1}{2}\vec{i}+\frac{\sqrt{3}}{2}\vec{j}}{2}$ in the directions North, $45^{o}$ South of West and $60^{o}$ North of West respectively.

So Total displacement vector = Sum of individual displacement vectors.

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Magnitude of Displacement = $|-4.25\vec{i}+3.165\vec{j}|=5.3km$

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3 years ago

We can block light by placing obstacles in its path, but it’s much more difficult to block sound. Why?

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3 years ago

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