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1 year ago

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A laser shines violet light with a frequency of 703 thz onto the metal with a threshold frequency of 295 thz, what is the kineti

c energy of the ejected electrons in ev? chegg

1 answer:

hram777 [196]1 year ago

3 0

The kinetic energy of the ejected electrons will be 2782.5 ×10⁻²² eV.

<h3>What is threshold frequency?</h3>

The threshold frequency of incoming radiation is the lowest frequency at which photoelectric emission or electron emission is impossible.

The threshold frequency is the light frequency that causes an electron to dislodge and emit from the metal's surface.

From the photoelectric effect, the equation obtained as;

$\rm hv=hv_0+KE\\\\ KE=h(v-v_0)\\\\ KE=6.625 \times 10^{-34}(702-282)Hz \\\\ KE= 6.625 \times 10^{-34}\times 420 \times 10^{12} \ Hz \\\\ KE=2782 .5 \times 10^{-22} \ eV$

Hence,the kinetic energy of the ejected electrons will be 2782.5 ×10⁻²² eV.

To learn more about the threshold frequency, refer to the link;

brainly.com/question/2499414

#SPJ1

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Explanation:

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a² = b²+c²......................... Equation 1

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Substitute these values into equation 1

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Explanation:

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2 years ago

A small meteorite with mass of 1 g strikes the outer wall of a communication satellite with a speed of 2Okm/s (relative to the s

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Explanation:

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Where:

$m_{M}$ , $m_{S}$ - Masses of the small meteorite and the communication satellite, measured in kilograms.

$v_{M}$ , $v_{S}$ - Speeds of the small meteorite and the communication satellite, measured in meters per second.

$v$ - Final speed of the satellite-meteorite system, measured in meters per second.

The final speed of the satellite-meteorite system is cleared:

$v = \frac{m_{M}\cdot v_{M}+m_{S}\cdot v_{S}}{m_{M}+m_{S}}$

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$v = \frac{(1\times 10^{-3}\,kg)\cdot \left(20000\,\frac{m}{s} \right)+(200\,kg)\cdot \left(0\,\frac{m}{s} \right)}{1\times 10^{-3}\,kg+200\,kg}$

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$K_{S}$ , $K_{M}$ - Initial translational kinetic energies of the communication satellite and small meteorite, measured in joules.

$K$ - Kinetic energy of the satellite-meteorite system, measured in joules.

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The energy coverted to heat is 200 kilojoules.

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