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Katyanochek1 [597]

3 years ago

7

HELP FAST MARKING BRAINLEST A neutral electroscope is touched with a positively charged rod. After the rod is removed the electr

oscope is charged positively because of: a. Induction b. Conduction c. Photoemission d. None from the above

1 answer:

ELEN [110]3 years ago

5 0

on touching electroscope gets positively charged, so answer is B. conduction

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How is solar impulse is different than conventional airplane

Nadusha1986 [10]

Answer:

Solar Impulse is a Swiss long-range experimental solar-powered aircraft project and Conventional Aircraft are the atmosphere-only aircraft that have been around since the Wright Flyer's first takeoff. Though modern craft are much more advanced and capable than that early model, Conventional Aircraft have been superseded in modern times by the AeroSpace Fighter, which can operate in both atmosphere and space.

Explanation:

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How many photons will be required to raise the temperature of 1.8 g of water by 2.5 k ?'?

tatyana61 [14]

Missing part in the text of the problem:
"<span>Water is exposed to infrared radiation of wavelength 3.0×10^−6 m"</span>

First we can calculate the amount of energy needed to raise the temperature of the water, which is given by
$Q=m C_s \Delta T$
where
m=1.8 g is the mass of the water
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Substituting the data, we find
$Q=(1.8 g)(4.18 J/(gK))(2.5 K)=18.8 J=E$

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where h is the Planck constant and f the frequency of the photon. Using the wavelength, we can find the photon frequency:
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So, the energy of a single photon of this frequency is
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and the number of photons needed is the total energy needed divided by the energy of a single photon:
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A boy weighs 40 kilograms. He runs at a velocity of 4 meters per second north. Which is his momentum?

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Other units for momentum is N s.
p = 160 N s

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3 years ago

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The term temperature has to do with the measure of an object's "hotness".

<h3>What is temperature?</h3>

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2 years ago

What are challenges of securing a crime scene

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<h3>What is the meaning of physical evidence?</h3>

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