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2 years ago

14

When an airplane flies from Dallas - Ft. Worth International airport to Los Angeles International airport, the time in the air i

s 2 hours and 36 minutes. The distance covered is 1246 miles" What is the average speed?

1 answer:

Elanso [62]2 years ago

7 0

Answer:

7.99 or 8 depends where you round.

Explanation:

Distance divided by time so 1246/156=7.98717948718

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A 45 kg man is running 22 m/s. Calculate the kinetic energy

Eddi Din [679]

Answer:

<h2>10890 J</h2>

Explanation:

The kinetic energy of an object can be found by using the formula

$k = \frac{1}{2} m {v}^{2} \\$

m is the mass

v is the velocity

From the question we have

$k = \frac{1}{2} \times 45 \times {22}^{2} \\ = \frac{1}{2} \times 45 \times 484 \\ = 45 \times 242 \\ = 10890$

We have the final answer as

<h3>10890 J</h3>

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Answer:

B

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Answer:

a

$n = 1.119 *10^{18} \ photons$

b

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Explanation:

From the question we are told that

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h is the Planck's constant with the value $h = 6.626 *10^{-34} \ J \cdot s$

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So

$n = \frac{E * \lambda }{h * c }$

substituting values

$n = \frac{80 *10^{-3} * 2780 *10^{-9}}{6.626 *10^{-34} * 3.0 *10^{8} }$

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Given that the pulses where emitted 20 times in one second then the period of the pulse is

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substituting values

$P = \frac{ 80 *10^{-3}}{0.05}$

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