# Worksheet: Electric Field of a Point Charge

In this worksheet, we will practice calculating the electrostatic force produced at a given distance from a point charge.

Q1:

The magnitude of an electric field is 100 N/C at a distance of 0.50 m from a point particle that has a charge of . What is the value of ?

• A C
• B C
• C C
• D C
• E C

Q2:

An electron is located m away from an alpha-particle. The alpha-particle has exactly double the charge of the electron.

What is the magnitude of the electric field due to the alpha-particle at the location of the electron?

• A N/C
• B N/C
• C N/C
• D N/C
• E N/C

What is the magnitude of the electric field due to the electron at the location of the alpha-particle?

• A N/C
• B N/C
• C N/C
• D N/C
• E N/C

What is the magnitude of the electric force on the alpha-particle?

• A N
• B N
• C N
• D N
• E N

What is the magnitude of the electric force on the electron?

• A N
• B N
• C N
• D N
• E N

Q3:

Earth has a net charge that produces an electric field aligned vertically downward at Earth’s surface. Assume a value of 150 N/C for the magnitude of the electric field and a value of 6,731 km for the radius of Earth.

What is the magnitude and sign of Earth’s excess charge, noting that the electric field of a conducting sphere is equivalent to a point charge at its center?

• A C
• B C
• C C
• D C
• E C

What is the magnitude of the acceleration that Earth’s electric field will produce on a free electron near Earth’s surface?

• A m/s2
• B m/s2
• C m/s2
• D m/s2
• E m/s2

What mass object with a single extra electron will have its weight supported by Earth’s electric field near Earth’s surface?

• A kg
• B kg
• C kg
• D kg
• E kg

Q4:

An electron orbiting in a hydrogen atom is separated from the atom’s nucleus by a distance of m.

What is the magnitude of the electric field of the nucleus at the point where the electron is located?

• A N/C
• B N/C
• C N/C
• D N/C
• E N/C

What is the magnitude of the electric force on the electron from the nucleus at the point where the electron is located?

• A N
• B N
• C N
• D N
• E N