Formula to find maximum kinetic energy?

In summary, the work function is 3.6 EV and the wavelength is 250nm UV. The maximum kinetic energy can be found using the formula KE=hc/λ – Φ, where Φ is the work function. This is due to the conservation of energy, where the energy of the incident photon is used to overcome the work function and the remaining energy goes into kinetic energy.
  • #1
Scippi
4
0

Homework Statement



Work Function=3.6 EV
Wavelength=250nm, UV
Maximum kinetic energy=?


Homework Equations



E=hf

Formulas from mark scheme:
E = hc/λ
hc/λ – Φ

The Attempt at a Solution



I had a vague idea of what to do, I just didn't understand why in the second formula from the mark scheme the work function is taken away from E
 
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  • #2
I haven't worked with this for a while, but isn't it just the conservation of energy? You are using the energy of the incident 250 nm photon to pull the particle from the surface (the work function) and the rest of the photon's energy goes into kinetic energy:
KE=hc/λ – Φ.
 
  • #3
It's so much simpler now that you've put it that way. Thank you so much! :'D
 

1. What is the formula to find maximum kinetic energy?

The formula to find maximum kinetic energy is KE = 1/2 * m * v^2, where KE is the kinetic energy, m is the mass of the object, and v is the velocity of the object.

2. How is kinetic energy related to an object's mass and velocity?

Kinetic energy is directly proportional to an object's mass and the square of its velocity. This means that as the mass or velocity of an object increases, its kinetic energy also increases.

3. Can the maximum kinetic energy of an object be negative?

No, the maximum kinetic energy of an object cannot be negative. This is because kinetic energy is a measure of an object's energy due to its motion, and negative energy is not physically possible.

4. How can the formula for maximum kinetic energy be applied in real-life situations?

The formula for maximum kinetic energy can be used to calculate the energy of moving objects in various scenarios, such as in physics experiments, sports, and engineering projects. It can also be used to determine the maximum speed of a vehicle or the energy required to launch a rocket.

5. Is there a limit to the maximum kinetic energy an object can have?

According to the laws of physics, there is no limit to the maximum kinetic energy an object can have. However, in practical situations, there are limitations based on factors such as the object's mass, velocity, and the environment it is in.

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