PHY2044 - PHYSICS FOR ENGINEERS II
PRACTICE TEST FOR CHAPTER 23

Below you will find a set of 5 conceptual and numerical revision questions selected randomly from lots of questions I have put together covering the material in Chapter 23, "Electric Potential". This includes questions on the electric potential for a system of charges and for continuous charge distributions, finding the potential from the electric field and equipotential surfaces. When you have finished the quiz, click on the "Submit Quiz" button at the bottom and within seconds it will be automatically graded and the results returned to you!

To select a new set of questions click on the "Reload" or "Refresh" button on your browser. You may find some of the questions duplicated but that's the nature of a random selection. Try it a few times ... it's not fattening and you may learn something!

Many thanks to Mark Wood for producing the quiz-maker code.


Q1: If the electric field is zero in some point in space then the electric potential is zero also.

True
False

Q2: Two parallel metal plates 5.0 cm apart have a potential difference between them of 75 V. The electric force on a positive charge of 3.2 × 10-19 C at a point midway between the plates is approximately

4.8 × 10-18 N
2.4 × 10-17 N
1.6 × 10-18 N
4.8 × 10-16 N
9.6 × 10-17 N

Q3: The figure below shows a uniform electric field.

The direction in which there is no change in the electric potential is

1
2
3
4
5


Q4: An isolated system consists of two conducting spheres A and B; the radius of A is five times the radius of sphere B. Initially, the spheres are given equal amounts of positive charge and are isolated from each other. The two spheres are then connected by a conducting wire. What is the ratio of the charge on sphere A to that on sphere B, qA/qB, after the spheres are connected by the wire?

1
1/5
5
25
1/25

Q5: The metal sphere at the top of a small Van de Graaf generator has a radius of 8.0 cm. How much charge can be accumulated on this sphere before dielectric breakdown of the air around it occurs? (The dielectric strength of air is 3.0 × 106 V/m.)

2.1 μC
3.3 μC
1.3 nC
6.7 μC
4.2 μC

Click on the Submit Quiz button below to have your quiz automatically graded.

Please note that you may be able to use the "Back" and "Forward" buttons on your browser to check the answers with the questions.