Coulomb's Law

• Physics
• Secondary Education

Lesson Objective

By the end of this lesson, you will be able to:

Explain Coulomb’s law in terms of the force proportionality with charge and distance.

Key Vocabulary

Elementary Charge

Excess Charge

Point Charges

Coulomb’s Law

Proportionality

Inverse-Square Proportionality

Which type of charging occurs when a charged object gently touches a metal neutral surface?

Induction

Conduction

A negatively charged rod is placed near the knob of a neutral electroscope. What happens?

1. both leaves become negatively charged and attract
2. both leaves become negatively charged and repel
3. both leaves become positively charged and attract
4. none of the above

The charge of an electron, -e =

1. -1.602 x 10^-19
2. 1.602 x 10^-17
3. 1.602 x 10^-19
4. 1.602 x 10^19

The K in Coulomb's law equation stands for the ___________.

1. Coulomb's constant
2. Number of excess electrons on the object
3. Radius of the spheres
4. Distance between the centers of the charged objects

Two spheres P and Q have an even charge distribution of 10 x 10 -6 C and
20 x 10 6 C and their centers are separated by 12 cm. What is the size and direction the electrostatic force acting on the particles?

Two spheres have an identical and even charge distribution of -6.25 x 10-9 C. They are held apart at a separation distance of 61.7 cm. Determine the magnitude and direction of the electrical force between them.

If we have 2-point charges, q1 and q2, that are 50 cm apart, what is the force exerted on q1 by q2 if we know that q1 has a charge of 10 µC and q2 has a charge of - 20 µC ?