A green leaf has a surface area of 2.50 cm². If solar radiation is 1000 W/m², how many photons strike the leaf every second? Assume three significant figures and an average wavelength of 504 nm for solar radiation.

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Convert the surface area of the leaf from cm² to m² by using the conversion factor: 1 cm² = 0.0001 m².

Calculate the total power of solar radiation striking the leaf by multiplying the solar radiation intensity (1000 W/m²) by the leaf's surface area in m².

Use the energy of a photon formula, \( E = \frac{hc}{\lambda} \), where \( h \) is Planck's constant (6.626 \times 10^{-34} \text{ J s}), \( c \) is the speed of light (3.00 \times 10^8 \text{ m/s}), and \( \lambda \) is the wavelength in meters (convert 504 nm to meters).

Calculate the number of photons by dividing the total power (in watts) by the energy of a single photon (in joules).

Ensure the final answer is expressed with three significant figures.

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In a technique used for surface analysis called Auger electron spectroscopy (AES), electrons are accelerated toward a metal surface. These electrons cause the emissions of secondary electrons—called Auger electrons—from the metal surface. The kinetic energy of the Auger electrons depends on the composition of the surface. The presence of oxygen atoms on the surface results in Auger electrons with a kinetic energy of approximately 506 eV. What is the de Broglie wavelength of one of these electrons? [KE = 1/2mv^2; 1 electron volt (eV) = 1.602 * 10^(-19) J]

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