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2 years ago

A runner runs 4875 ft in 6.85 minutes. what is the runners average speed in miles per hour?

Physics

2 answers:

yanalaym [24]2 years ago

8 0

The average speed can be easily calculated by taking the ratio of distance and time. That is:

average speed = distance / time

so calculating:

average speed = 4875 ft / 6.85 minutes

<span>average speed = 711.68 ft / min</span>

zaharov [31]2 years ago

7 0

<u>Answer</u>:

Speed of the runner is 8.08 miles per hour approximately.

<u>Explanation</u>:

Given:

A runner runs =4875 ft

Time Taken = 6.85 minutes.

To Find:

Average speed of the runner in miles per hour=?

Solution:

Distance = Speed x time

Conveting feet into miles:

=>Distance= $4875\times\frac{1}{5280}$ miles

=>Distance = 0.9232955 miles

Converting minutes into hours:

time = 6.85 minutes

=> $6.85\times \frac{1}{60}$ hours

=> $\frac{6.85}{60}$ = 0.1141667 hours.

Now, we know that, distance = speed x time

Then, 0.9232955 miles = speed x 0.1141667 hours

=>speed = $\frac{0.9232955}{0.1141667}$

=>speed = 8.08725749

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Answer:

Power, P = 924.15 watts

Explanation:

Given that,

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2 years ago

A 10-kg dog is running with a speed of 5.0 m/s. what is the minimum work required to stop the dog in 2.40 s?

Tasya [4]

<h3><u>Answer;</u></h3>

<em>Work = 125 joules </em>

<h3><u>Explanation and solution</u>;</h3>

Work is the product of force and the distance covered. Therefore, Work = force × distance.

Work is measured in joules.
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2 years ago

Draw the vector C⃗ =1.5A⃗ −3B⃗ . The length and orientation of the vector will be graded. The location of the vector is not impo

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I made the drawing in the attached file.

I included two figures.

The upper figure shows the effect of:

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It is drawn in red with dotted line.

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It is drawn in purple with dotted line.

In the lower figure you have the resultant vector: C = 1.5A - 3B.

The method is that you translate the tail of the vector -3B unitl the point of the vector 1,5A, preserving the angles.

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2 years ago

Read 2 more answers

If the briefcase hits the water 6.0 s later, what was the speed at which the helicopter was ascending?

vovikov84 [41]

Complete Question

In an action movie, the villain is rescued from the ocean by grabbing onto the ladder hanging from a helicopter. He is so intent on gripping the ladder that he lets go of his briefcase of counterfeit money when he is 130 m above the water. If the briefcase hits the water 6.0 s later, what was the speed at which the helicopter was ascending?

Answer:

The speed of the helicopter is $u = 7.73 \ m/s$

Explanation:

From the question we are told that

The height at which he let go of the brief case is h = 130 m

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$s = h+ u t + 0.5 gt^2$