Examine the scenario.
A piece of metal is exposed to light of a high and low frequency.
Which statement correctly predicts how the metal will respond to the light and explains the metal's behavior?
When exposed to high frequency light, the metal will give off fewer electrons because higher frequency light is lower in energy.
When exposed to low frequency light, the metal will give off more electrons because lower frequency light is higher in energy.
When exposed to high frequency light, the metal will give off more electrons because higher frequency light is higher in energy.
When exposed to low frequency light, the metal will give off fewer electrons because lower frequency light is lower in energy.
To determine which statement correctly predicts how the metal will respond to the light, we need to understand the concept of the photoelectric effect. The photoelectric effect is the emission of electrons from a material (such as a metal) when it is exposed to light.
According to the photoelectric effect, light is made up of particles called photons, and each photon carries a specific amount of energy. The energy of a photon is directly proportional to its frequency (the number of wave crests passing a specific point per second). Higher frequency light has more energy per photon compared to lower frequency light.
Now, let's examine the four statements:
1. "When exposed to high frequency light, the metal will give off fewer electrons because higher frequency light is lower in energy."
2. "When exposed to low frequency light, the metal will give off more electrons because lower frequency light is higher in energy."
3. "When exposed to high frequency light, the metal will give off more electrons because higher frequency light is higher in energy."
4. "When exposed to low frequency light, the metal will give off fewer electrons because lower frequency light is lower in energy."
Based on the photoelectric effect, statement 3 is the correct prediction. When exposed to high frequency light, the metal will give off more electrons because higher frequency light carries more energy per photon. This extra energy is required to overcome the binding forces holding the electrons in the metal, allowing them to be released.
It's also worth noting that the number of electrons emitted by the metal depends not only on the energy of the incoming photons but also on the properties of the metal itself, such as its work function or the threshold energy required to release electrons.