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In an advanced laboratory class a student performs the photoelectric experiment, Ultraviolet ight is shone on a particular metal and the stopping potential is measured at the same time, It is found that 4.04 V is needed to stop all the electrons when the wavelength of the light is 268 nm, and 4.71 V for a waveiength finds wim what is the work function of the metar? Thes 0/12 What ie Dlanrk's ranstant based on this measurement? Tries 0/12

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Final answer:

The work function of a metal can be calculated using the stopping potential and electron charge. The cutoff frequency can be calculated using the speed of light and wavelength. Planck's constant can be determined using the work function and cutoff frequency.

Step-by-step explanation:

The work function of a metal is the minimum amount of energy needed to remove an electron from the surface of the metal. It can be calculated using the equation:

Work function (Φ) = Stopping potential (V) × electron charge (e)

The cutoff frequency of the surface can be calculated using the equation:

Cutoff frequency (f) = Speed of light (c) / wavelength (λ)

Based on the given measurements, the work function of the metal can be calculated by solving the equation:

4.04 V = Φ/e

The cutoff frequency can be calculated using the equation:

f = c/268 nm

And by calculating the work function and the cutoff frequency, Planck's constant can be determined using the equation:

Planck's constant (h) = Φ × f

Using the same method, all the other questions can be solved.

User Wwward
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Final answer:

The work function of a metal is the minimum energy needed to remove an electron from the surface of the metal. The cutoff frequency of a surface is the minimum frequency of light required to emit electrons from the surface. To find the work function and cutoff frequency, we can use the equations relating them to each other and other known values.

Step-by-step explanation:

The work function of a metal is the minimum energy needed to remove an electron from the surface of the metal. It is represented by the symbol Φ. The cutoff frequency of a surface is the minimum frequency of light required to emit electrons from the surface. It is related to the work function by the equation:

fcutoff = (Φ / h) x c

where fcutoff is the cutoff frequency, Φ is the work function, h is Planck's constant (6.626 x 10^-34 J s), and c is the speed of light (3.00 x 10^8 m/s).

To find the work function, we can rearrange the equation and solve for Φ:

Φ = (fcutoff x h) / c

Using the given wavelength of 400 nm (or 4.00 x 10^-7 m), we can convert it to frequency using the equation:

f = c / λ

Substituting the values into the equation, we can calculate the cutoff frequency:

fcutoff = (3.00 x 10^8 m/s) / (4.00 x 10^-7 m) = 7.50 x 10^14 Hz

Finally, substituting the values into the rearranged equation, we can calculate the work function:

Φ = (7.50 x 10^14 Hz x 6.626 x 10^-34 J s) / (3.00 x 10^8 m/s) = 1.66 x 10^-19 J

User Brayan Caldera
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