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2 years ago

8

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]2 years 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

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$v_f = \frac{7.5 \frac{kg m^2}{s}}{ 0.250 m * 2.00 kg}$

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