# Worksheet: The Electron Volt

In this worksheet, we will practice defining the unit of an electron volt and converting between electron volts and other energy units.

**Q1: **

What is J in kilo-electron volts?

**Q2: **

What is 14 eV in joules? Give your answer to 3 significant figures.

- A J
- B J
- C J
- D J
- E J

**Q3: **

What is 30 keV in joules?

- A0.030 J
- B J
- C J
- D J
- E J

**Q4: **

What is J in electron volts?

**Q5: **

How many electron volts are in 1 keV?

**Q6: **

What is J in mega-electron volts ?

**Q7: **

How many electron volts are in 1 MeV?

- A
- B
- C
- D
- E

**Q8: **

An electron is accelerated across a potential difference of V. The electron moves in a vacuum. What is the kinetic energy, in electron volts, of the electron once it has crossed this potential difference?

**Q9: **

What is 930 MeV in joules?

- A J
- B J
- C J
- D J
- E930 J

**Q10: **

How many giga-electron volts are there in 1 J? Use a value of C for the charge of one electron.

- A GeV
- B GeV
- C GeV
- D GeV
- E GeV

**Q11: **

An electron is accelerated across a potential difference of exactly V. The electron moves in a vacuum.

What is the kinetic energy, in joules, of the electron once it has crossed this potential difference? Use a value of for the charge of an electron.

- A J
- B J
- C J
- D J
- E1.00 J

If this value of energy is used as a unit (electron volt, eV), what is the kinetic energy of the electron once it has crossed the potential difference, in electron volts?

- A eV
- B eV
- C1.00 eV
- D eV
- E0.500 eV