# How Charged Objects Interact

IQ: How do charged objects interact with other charged objects and with neutral
objects?

• Electrostatic force
• Process of how objects become electrically charged
• Interactions between charged particles
• Electric field lines
• simple point charges
• pairs of charges
• dipoles
• parallel charged plates
• 𝐹 = 𝑞𝐸 and 𝐸 =𝑉𝑑 and 𝐹 =(1/4𝜋𝜀)*(𝑞1𝑞2/𝑟^2)

Learn.

Master.

Question 1.

Diagrammatically, compare and contrast the interaction between two positive point charges, two negative point charges and a positive and negative point charge. [3 marks]

Question 2.

A student rubs a balloon against their head and notices the balloon sticks to their head, explain this phenomena. [3 marks]

Question 3.

Draw the path of an electron passing between a pair of charged plates, arrange the plates so the field lines are parallel to the horizon. [2 marks]

Question 4.

• a) A charged plate has a 4 V potential difference with a spacing of 15 cm, if an electron is released midway between the plates, what is the maximum acceleration of the electron. [4 marks]
• b) What is it’s maximum velocity [2 marks]
• c) How would this differ if the electron was replaced by a proton. [4 marks]

Question 5.

A helium nucleus, consisting of two protons and two neutrons, is 5 cm from a proton.

• a) Will this experience an attractive force or a repulsive force [1 mark]
• b) What will be the magnitude of this force? [2 marks]

Questions 1.

• include diagram of like charges as well.

Question 4.

• a) 4.7 * 1012 m/s/s towards positive
• b) 8 * 106 m/s towards positive
• c) Repeat calculations accounting for different mass and charge.

Question 5.

1.84 * 10^-29 N repulsion