Light is shone on a metal and photoelectrons are emitted.
Can you tell me the three things from the listbelow which might cause the photoelectron emission to stop.
Decreasing the intensity of the light
Increasing the frequency of the light
Decreasing the wavelength of the light
Increasing the wavelength of the light
Changing the metal
Decreasing the frequency of the light
Increasing the intensity of the light
A bouncy rubber ball is dropped from a height of about a metre above the ground .it falls to the ground, bounces and then rises back to almost the height from which it was dropped. Describe the main energy transformations that take place from the point at which the ball first touches the ground until the point it leaves the ground again.
Gravitational potential energy is converted into kinetic energy and then into sound energy.
Is that correct help plz
Increasing the wavelength of the light,
Changing the metal,
Decreasing the frequency of the light
To determine the three things that might cause the photoelectron emission to stop, we need to understand the factors that affect the phenomenon of photoelectric effect. The photoelectric effect occurs when photons (light particles) transfer their energy to electrons in a metal, causing them to be ejected from the surface.
Now, let's analyze each option to see whether it would cause the photoelectron emission to stop or not:
1. Decreasing the intensity of the light: This would not cause the emission to stop, but it would decrease the number of emitted photoelectrons. In other words, reducing the intensity would result in fewer electrons being emitted, but the effect would still occur.
2. Increasing the frequency of the light: The photoelectric effect depends on the energy of the incident photons, which is directly related to their frequency. Increasing the frequency of light would result in higher-energy photons, which could potentially cause more electrons to be emitted. Therefore, increasing the frequency would not cause the emission to stop.
3. Decreasing the wavelength of the light: Since wavelength and frequency are inversely related (c = λν, where c is the speed of light), decreasing the wavelength would increase the frequency of the light. As mentioned earlier, increasing the frequency would not stop the photoelectron emission; instead, it would likely cause more electrons to be emitted. Therefore, decreasing the wavelength would not stop the emission.
4. Increasing the wavelength of the light: This would decrease the frequency of the light, as mentioned before. Since photoelectron emission occurs when photons transfer energy to electrons, decreasing the frequency/energy of the incident photons would likely make it more difficult for electrons to be emitted. Therefore, increasing the wavelength could potentially stop the emission.
5. Changing the metal: The photoelectric effect is specific to the metal being used. Different metals have different energy bands and work functions, which affect their ability to emit electrons. Changing the metal could, therefore, potentially stop the photoelectron emission, especially if the new metal has a much higher work function or a different energy band structure.
6. Decreasing the frequency of the light: As discussed before, increasing the frequency would provide higher-energy photons that are more likely to cause photoelectron emission. Conversely, decreasing the frequency would result in lower-energy photons, making it less likely for electrons to be emitted. Therefore, decreasing the frequency could potentially stop the emission.
7. Increasing the intensity of the light: Similar to the first scenario, increasing the intensity would not stop the emission but would cause more electrons to be emitted.
To summarize, the three things that might cause photoelectron emission to stop from the given options are:
1. Increasing the wavelength of the light.
2. Changing the metal.
3. Decreasing the frequency of the light.